| **Reinsurance (Details) (USD $)**                                                    | 12 Months Ended                                                                                                                                                          | 0 Months Ended                                                                                                                                                           |
|--------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
||
| **Insurance [Abstract]**                                                             |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| Initial maximum coverage, per individual life retained                               | $ 3,500,000gac_InitialMaximumLiabilityOfCoveragePerIndividualLifeRetained                                                                                                |                                                                                                                                                                     |   |   |
| Maximum annual growth due to automatic policy increases in coverage, per annum       | 175,000gac_MaximumAnnualGrowthInMaximumLiabilityOfCoveragePerIndividualLifeRetained                                                                                      |                                                                                                                                                                     |   |   |
| Overall maximum growth due to automatic increase in coverage                         | 1,000,000gac_ThresholdLimitOfOverallGrowthInMaximumLiabilityOfCoveragePerIndividualLifeRetained                                                                          |                                                                                                                                                                     |   |   |
| Reinsurance receivable                                                               | 611,270,000us-gaap_ReinsuranceRecoverables                                                                                                                               | 588,533,000us-gaap_ReinsuranceRecoverables                                                                                                                               |   |   |
| Reinsurance receivables, associated with reinsurance agreements with related parties | 529,921,000gac_RelatedPartyTransactionReinsuranceRecoverables                                                                                                            | 502,471,000gac_RelatedPartyTransactionReinsuranceRecoverables                                                                                                            |   |   |
| Number of insurers and reinsurers from whom risk is assumed, in counterparties       | 40gac_NumberOfInsurersAndReinsurersFromWhomRiskAssumed                                                                                                                   |                                                                                                                                                                     |   |   |
| **Life insurance in-force and total premium income**                                 |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| Life insurance and annuity future benefits with life contingencies                   | 15,349,322,000us-gaap_LiabilityForFuturePolicyBenefitsLife                                                                                                               | 14,296,153,000us-gaap_LiabilityForFuturePolicyBenefitsLife                                                                                                               |   |   |
| **Life insurance in-force**                                                          |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| Written and earned direct                                                            | 94,104,689,000us-gaap_DirectPremiumsLifeInsuranceInForce                                                                                                                 | 92,180,904,000us-gaap_DirectPremiumsLifeInsuranceInForce                                                                                                                 |   |   |
| Reinsurance ceded                                                                    | (9,773,885,000)us-gaap_CededPremiumsLifeInsuranceInForce                                                                                                                 | (9,512,583,000)us-gaap_CededPremiumsLifeInsuranceInForce                                                                                                                 |   |   |
| Reinsurance assumed                                                                  | 61,911,865,000us-gaap_AssumedPremiumsLifeInsuranceInForce                                                                                                                | 66,209,732,000us-gaap_AssumedPremiumsLifeInsuranceInForce                                                                                                                |   |   |
| Net                                                                                  | 146,242,669,000us-gaap_PremiumsNetLifeInsuranceInForce                                                                                                                   | 148,878,053,000us-gaap_PremiumsNetLifeInsuranceInForce                                                                                                                   |   |   |
| Percentage of amount assumed to net                                                  | 42.00%us-gaap_LifeInsuranceInForcePremiumsPercentageAssumedToNet                                                                                                         | 44.00%us-gaap_LifeInsuranceInForcePremiumsPercentageAssumedToNet                                                                                                         |   |   |
| **Premium income**                                                                   |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| Net                                                                                  | 446,395,000us-gaap_PremiumsEarnedNet                                                                                                                                     | 464,093,000us-gaap_PremiumsEarnedNet                                                                                                                                     | 422,153,000us-gaap_PremiumsEarnedNet |   |
| Life and other policy benefits, reinsurance recoveries                               | 23,965,000us-gaap_ReinsuranceCostsAndRecoveriesNet                                                                                                                       | 34,716,000us-gaap_ReinsuranceCostsAndRecoveriesNet                                                                                                                       | 46,492,000us-gaap_ReinsuranceCostsAndRecoveriesNet |   |
| Maximum                                                                              |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| **Life insurance in-force and total premium income**                                 |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| Life insurance and annuity future benefits with life contingencies                   | 4,500,000us-gaap_LiabilityForFuturePolicyBenefitsLife/ us-gaap_RangeAxis= us-gaap_MaximumMember                                                                          |                                                                                                                                                                     |   |   |
| CLAC                                                                                 |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| **Insurance [Abstract]**                                                             |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| Reinsurance receivable                                                               |                                                                                                                                                                     |                                                                                                                                                                     |   | (42,297,000)us-gaap_ReinsuranceRecoverables/ us-gaap_RelatedPartyTransactionsByRelatedPartyAxis= gac_CanadaLifeAssuranceCompanyMember |
| **Life insurance in-force and total premium income**                                 |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| Total reinsurance receivable due from CLAC, a related party (as a percent)           | 87.00%us-gaap_ReinsuranceRecoverablesPercentageOfTotal/ us-gaap_RelatedPartyTransactionsByRelatedPartyAxis= gac_CanadaLifeAssuranceCompanyMember                         | 85.00%us-gaap_ReinsuranceRecoverablesPercentageOfTotal/ us-gaap_RelatedPartyTransactionsByRelatedPartyAxis= gac_CanadaLifeAssuranceCompanyMember                         |   |   |
| **Premium income**                                                                   |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| Net                                                                                  |                                                                                                                                                                     |                                                                                                                                                                     |   | 42,297,000us-gaap_PremiumsEarnedNet/ us-gaap_RelatedPartyTransactionsByRelatedPartyAxis= gac_CanadaLifeAssuranceCompanyMember |
| Individual                                                                           |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| **Life insurance in-force**                                                          |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| Written and earned direct                                                            | 52,836,475,000us-gaap_DirectPremiumsLifeInsuranceInForce/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_IndividualPoliciesMember         | 51,660,487,000us-gaap_DirectPremiumsLifeInsuranceInForce/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_IndividualPoliciesMember         |   |   |
| Reinsurance ceded                                                                    | (9,773,885,000)us-gaap_CededPremiumsLifeInsuranceInForce/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_IndividualPoliciesMember         | (9,512,583,000)us-gaap_CededPremiumsLifeInsuranceInForce/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_IndividualPoliciesMember         |   |   |
| Reinsurance assumed                                                                  | 61,911,865,000us-gaap_AssumedPremiumsLifeInsuranceInForce/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_IndividualPoliciesMember        | 66,209,732,000us-gaap_AssumedPremiumsLifeInsuranceInForce/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_IndividualPoliciesMember        |   |   |
| Net                                                                                  | 104,974,455,000us-gaap_PremiumsNetLifeInsuranceInForce/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_IndividualPoliciesMember           | 108,357,636,000us-gaap_PremiumsNetLifeInsuranceInForce/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_IndividualPoliciesMember           |   |   |
| Percentage of amount assumed to net                                                  | 59.00%us-gaap_LifeInsuranceInForcePremiumsPercentageAssumedToNet/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_IndividualPoliciesMember | 61.00%us-gaap_LifeInsuranceInForcePremiumsPercentageAssumedToNet/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_IndividualPoliciesMember |   |   |
| Group                                                                                |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| **Life insurance in-force**                                                          |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| Written and earned direct                                                            | 41,268,214,000us-gaap_DirectPremiumsLifeInsuranceInForce/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_GroupPoliciesMember              | 40,520,417,000us-gaap_DirectPremiumsLifeInsuranceInForce/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_GroupPoliciesMember              |   |   |
| Reinsurance ceded                                                                    |                                                                                                                                                                     | 0us-gaap_CededPremiumsLifeInsuranceInForce/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_GroupPoliciesMember                            |   |   |
| Reinsurance assumed                                                                  |                                                                                                                                                                     | 0us-gaap_AssumedPremiumsLifeInsuranceInForce/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_GroupPoliciesMember                          |   |   |
| Net                                                                                  | 41,268,214,000us-gaap_PremiumsNetLifeInsuranceInForce/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_GroupPoliciesMember                 | 40,520,417,000us-gaap_PremiumsNetLifeInsuranceInForce/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_GroupPoliciesMember                 |   |   |
| Percentage of amount assumed to net                                                  | 0.00%us-gaap_LifeInsuranceInForcePremiumsPercentageAssumedToNet/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_GroupPoliciesMember       | 0.00%us-gaap_LifeInsuranceInForcePremiumsPercentageAssumedToNet/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_GroupPoliciesMember       |   |   |
| Premium Income                                                                       |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| **Premium income**                                                                   |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| Written and earned direct                                                            | 362,214,000us-gaap_DirectPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= gac_PremiumIncomeMember                                   | 319,100,000us-gaap_DirectPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= gac_PremiumIncomeMember                                   | 326,948,000us-gaap_DirectPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= gac_PremiumIncomeMember |   |
| Reinsurance ceded                                                                    | (46,020,000)us-gaap_CededPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= gac_PremiumIncomeMember                                   | (1,426,000)us-gaap_CededPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= gac_PremiumIncomeMember                                    | (50,302,000)us-gaap_CededPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= gac_PremiumIncomeMember |   |
| Reinsurance assumed                                                                  | 130,201,000us-gaap_AssumedPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= gac_PremiumIncomeMember                                  | 146,419,000us-gaap_AssumedPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= gac_PremiumIncomeMember                                  | 145,507,000us-gaap_AssumedPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= gac_PremiumIncomeMember |   |
| Net                                                                                  | 446,395,000us-gaap_PremiumsEarnedNet/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= gac_PremiumIncomeMember                                      | 464,093,000us-gaap_PremiumsEarnedNet/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= gac_PremiumIncomeMember                                      | 422,153,000us-gaap_PremiumsEarnedNet/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= gac_PremiumIncomeMember |   |
| Life insurance                                                                       |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| **Premium income**                                                                   |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| Written and earned direct                                                            | 360,959,000us-gaap_DirectPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_LifeInsuranceSegmentMember                        | 315,100,000us-gaap_DirectPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_LifeInsuranceSegmentMember                        | 323,236,000us-gaap_DirectPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_LifeInsuranceSegmentMember |   |
| Reinsurance ceded                                                                    | (45,925,000)us-gaap_CededPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_LifeInsuranceSegmentMember                        | (1,338,000)us-gaap_CededPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_LifeInsuranceSegmentMember                         | (53,950,000)us-gaap_CededPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_LifeInsuranceSegmentMember |   |
| Reinsurance assumed                                                                  | 130,201,000us-gaap_AssumedPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_LifeInsuranceSegmentMember                       | 146,419,000us-gaap_AssumedPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_LifeInsuranceSegmentMember                       | 145,507,000us-gaap_AssumedPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_LifeInsuranceSegmentMember |   |
| Net                                                                                  | 445,235,000us-gaap_PremiumsEarnedNet/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_LifeInsuranceSegmentMember                           | 460,181,000us-gaap_PremiumsEarnedNet/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_LifeInsuranceSegmentMember                           | 414,793,000us-gaap_PremiumsEarnedNet/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_LifeInsuranceSegmentMember |   |
| Annuities                                                                            |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| **Premium income**                                                                   |                                                                                                                                                                     |                                                                                                                                                                     |   |   |
| Written and earned direct                                                            | 1,255,000us-gaap_DirectPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_VariableAnnuityMember                               | 4,000,000us-gaap_DirectPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_VariableAnnuityMember                               | 3,712,000us-gaap_DirectPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_VariableAnnuityMember |   |
| Reinsurance ceded                                                                    | (95,000)us-gaap_CededPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_VariableAnnuityMember                                 | (88,000)us-gaap_CededPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_VariableAnnuityMember                                 | 3,648,000us-gaap_CededPremiumsEarned/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_VariableAnnuityMember |   |
| Net                                                                                  | $ 1,160,000us-gaap_PremiumsEarnedNet/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_VariableAnnuityMember                                | $ 3,912,000us-gaap_PremiumsEarnedNet/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_VariableAnnuityMember                                | $ 7,360,000us-gaap_PremiumsEarnedNet/ us-gaap_ReinsurancePremiumsForInsuranceCompaniesByProductSegmentAxis= us-gaap_VariableAnnuityMember |   |

| X                                                                                                                                                                                                                                                                                                                                                                               |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents the initial maximum liability of coverage per individual life retained by the entity under the reinsurance agreement.
+ References
No definition available.
+ Details**Name:**gac_InitialMaximumLiabilityOfCoveragePerIndividualLifeRetained**Namespace Prefix:**gac_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents the maximum annual growth in maximum liability of coverage per individual life claim retained by the entity under the insurance arrangement due to automatic increases.
+ References
No definition available.
+ Details**Name:**gac_MaximumAnnualGrowthInMaximumLiabilityOfCoveragePerIndividualLifeRetained**Namespace Prefix:**gac_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                         |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents the number of insurers and reinsurers from whom risk is assumed by the entity.
+ References
No definition available.
+ Details**Name:**gac_NumberOfInsurersAndReinsurersFromWhomRiskAssumed**Namespace Prefix:**gac_**Data Type:**xbrli:integerItemType**Balance Type:**na**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The known and estimated amount recoverable, as of the balance sheet date, from reinsurers for claims paid or incurred by the ceding insurer and associated claims settlement expenses, including estimated amounts for claims incurred but not reported, and policy benefits, net of any related valuation allowance, arising from transactions with related parties.
+ References
No definition available.
+ Details**Name:**gac_RelatedPartyTransactionReinsuranceRecoverables**Namespace Prefix:**gac_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents the threshold limit of overall growth in maximum liability of coverage per individual life claim retained by the entity under the insurance arrangement due to automatic increases.
+ References
No definition available.
+ Details**Name:**gac_ThresholdLimitOfOverallGrowthInMaximumLiabilityOfCoveragePerIndividualLifeRetained**Namespace Prefix:**gac_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of earned premiums assumed from other entities.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 17 -Article 12Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17) -URI http://asc.fasb.org/extlink&oid=6588446&loc=d3e574992-122915Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.1) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 1 -Subparagraph (b),(c)(2) -URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 1 -Article 7
+ Details**Name:**us-gaap_AssumedPremiumsEarned**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of life insurance in force premiums assumed from other entities.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 17 -Article 12Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17) -URI http://asc.fasb.org/extlink&oid=6588446&loc=d3e574992-122915
+ Details**Name:**us-gaap_AssumedPremiumsLifeInsuranceInForce**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of earned premiums ceded to other entities.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 17 -Article 12Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17) -URI http://asc.fasb.org/extlink&oid=6588446&loc=d3e574992-122915Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.1) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 1 -Subparagraph (b),(c)(2) -URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 1 -Article 7Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6486662&loc=d3e27175-158546
+ Details**Name:**us-gaap_CededPremiumsEarned**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of life insurance in force premiums ceded to other entities.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 17 -Article 12Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17) -URI http://asc.fasb.org/extlink&oid=6588446&loc=d3e574992-122915
+ Details**Name:**us-gaap_CededPremiumsLifeInsuranceInForce**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums earned.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 17 -Article 12Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17) -URI http://asc.fasb.org/extlink&oid=6588446&loc=d3e574992-122915Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.1) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 1 -Article 7Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 1 -Subparagraph (b),(c)(1) -URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount, before premiums ceded to other entities and premiums assumed by the entity, of life insurance in force premiums.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 17 -Article 12Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17) -URI http://asc.fasb.org/extlink&oid=6588446&loc=d3e574992-122915
+ Details**Name:**us-gaap_DirectPremiumsLifeInsuranceInForce**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**duration |
| X                                                                                                                                                     |
|-------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_InsuranceAbstract**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of accrued obligation to policyholders that relates to insured events under long-term life insurance contracts.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 25 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=28366191&loc=d3e13145-158430Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 13 -Subparagraph a -Article 7Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.13(a)(1)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910
+ Details**Name:**us-gaap_LiabilityForFuturePolicyBenefitsLife**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Percentage of assumed life insurance in force premiums to net premiums.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 17 -Article 12Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17) -URI http://asc.fasb.org/extlink&oid=6588446&loc=d3e574992-122915
+ Details**Name:**us-gaap_LifeInsuranceInForcePremiumsPercentageAssumedToNet**Namespace Prefix:**us-gaap_**Data Type:**num:percentItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 17 -Article 12Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17) -URI http://asc.fasb.org/extlink&oid=6588446&loc=d3e574992-122915Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.1) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 1 -Article 7Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13(c)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount, after premiums ceded to other entities and premiums assumed by the entity, of life insurance in force premiums.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 17 -Article 12Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17) -URI http://asc.fasb.org/extlink&oid=6588446&loc=d3e574992-122915
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of recovery (expense) related to provision for policy benefits and costs incurred for policies assumed and ceded.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437
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| X                                                                                                                                                                                                     |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                                             |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount after valuation allowance recoverable including premium paid under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 6 -Article 7Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 20 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6480758&loc=d3e6824-158387Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.(a),6) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910
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| X                                                                                                                                                                                                                                                                           |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Percentage of total reinsurance recoverables.
+ References
No definition available.
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| X                                                                                                                               |
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| X                                                                                                                                                                                    |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                        |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                             |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                               |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                          |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                               |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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