| **Segment Information (Details) $ in Thousands** | 3 Months Ended | 9 Months Ended |
|--------------------------------------------------|----------------|----------------|
||
| **Financial information of the segments**        |           |           |   |   |
| Number of reportable segments | segment          |           |           | 3 |   |
| **Revenues**                                     |           |           |   |   |
| Premium income                                   | $ 146,100      | $ 154,017      | $ 377,845 | $ 374,437 |
| Fee income                                       | 246,413        | 225,242        | 709,844 | 688,020 |
| Other revenue                                    | 3,228          | 1,820          | 9,747 | 5,460 |
| Net investment income                            | 291,539        | 363,057        | 979,080 | 942,082 |
| Realized investment gains (losses), net          | 33,374         | 22,551         | 106,657 | 56,610 |
| Total revenues                                   | 720,654        | 766,687        | 2,183,173 | 2,066,609 |
| **Benefits and expenses:**                       |           |           |   |   |
| Policyholder benefits                            | 346,861        | 357,614        | 946,876 | 957,603 |
| Operating expenses                               | 318,481        | 310,792        | 944,815 | 870,908 |
| Total benefits and expenses                      | 665,342        | 668,406        | 1,891,691 | 1,828,511 |
| Income before income taxes                       | 55,312         | 98,281         | 291,482 | 238,098 |
| Income tax expense                               | 15,295         | 30,708         | 79,043 | 78,926 |
| Net income                                       | 40,017         | 67,573         | 212,439 | 159,172 |
| Operating Segments | Individual Markets          |           |           |   |   |
| **Revenues**                                     |           |           |   |   |
| Premium income                                   | 126,770        | 132,761        | 311,110 | 308,976 |
| Fee income                                       | 23,553         | 19,745         | 71,823 | 66,214 |
| Other revenue                                    | 0              | 0              | 0 | 0 |
| Net investment income                            | 185,747        | 222,445        | 619,633 | 595,757 |
| Realized investment gains (losses), net          | 11,026         | 8,304          | 37,602 | 20,256 |
| Total revenues                                   | 347,096        | 383,255        | 1,040,168 | 991,203 |
| **Benefits and expenses:**                       |           |           |   |   |
| Policyholder benefits                            | 280,821        | 270,614        | 749,790 | 725,526 |
| Operating expenses                               | 35,948         | 49,407         | 127,181 | 116,770 |
| Total benefits and expenses                      | 316,769        | 320,021        | 876,971 | 842,296 |
| Income before income taxes                       | 30,327         | 63,234         | 163,197 | 148,907 |
| Income tax expense                               | 10,102         | 21,539         | 55,183 | 51,262 |
| Net income                                       | 20,225         | 41,695         | 108,014 | 97,645 |
| Operating Segments | Empower Retirement          |           |           |   |   |
| **Revenues**                                     |           |           |   |   |
| Premium income                                   | 605            | 477            | 1,311 | 493 |
| Fee income                                       | 221,342        | 204,488        | 633,679 | 618,841 |
| Other revenue                                    | 3,228          | 1,820          | 9,747 | 5,460 |
| Net investment income                            | 94,383         | 127,160        | 321,972 | 305,969 |
| Realized investment gains (losses), net          | 21,565         | 14,247         | 68,278 | 36,257 |
| Total revenues                                   | 341,123        | 348,192        | 1,034,987 | 967,020 |
| **Benefits and expenses:**                       |           |           |   |   |
| Policyholder benefits                            | 51,730         | 54,401         | 153,587 | 151,194 |
| Operating expenses                               | 263,327        | 242,841        | 761,827 | 704,047 |
| Total benefits and expenses                      | 315,057        | 297,242        | 915,414 | 855,241 |
| Income before income taxes                       | 26,066         | 50,950         | 119,573 | 111,779 |
| Income tax expense                               | 5,442          | 14,884         | 20,579 | 35,651 |
| Net income                                       | 20,624         | 36,066         | 98,994 | 76,128 |
| Operating Segments | Other                       |           |           |   |   |
| **Revenues**                                     |           |           |   |   |
| Premium income                                   | 18,725         | 20,779         | 65,424 | 64,968 |
| Fee income                                       | 1,518          | 1,009          | 4,342 | 2,965 |
| Other revenue                                    | 0              | 0              | 0 | 0 |
| Net investment income                            | 11,409         | 13,452         | 37,475 | 40,356 |
| Realized investment gains (losses), net          | 783            | 0              | 777 | 97 |
| Total revenues                                   | 32,435         | 35,240         | 108,018 | 108,386 |
| **Benefits and expenses:**                       |           |           |   |   |
| Policyholder benefits                            | 14,310         | 32,599         | 43,499 | 80,883 |
| Operating expenses                               | 19,206         | 18,544         | 55,807 | 50,091 |
| Total benefits and expenses                      | 33,516         | 51,143         | 99,306 | 130,974 |
| Income before income taxes                       | (1,081)        | (15,903)       | 8,712 | (22,588) |
| Income tax expense                               | (249)          | (5,715)        | 3,281 | (7,987) |
| Net income                                       | $ (832)        | $ (10,188)     | $ 5,431 | $ (14,601) |

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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The total amount of expense recognized during the period for future policy benefits, claims and claims adjustment costs, which also includes interest to contract holders, dividends to policyholders and provision (benefit) for policyholders' share of earnings in the participating business during the period.
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| - Definition
The total amount of expense recognized during the period for future policy benefits, claims and claims adjustment costs, and for selling, general and administrative costs.
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| - Definition
Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.
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| - Definition
Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Income from agency and brokerage operations (includes sales of annuities and supplemental contracts); service charges, commissions, and fees from the sale of insurance and related services; and management fees from separate accounts, deferred annuities, and universal life products.
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| - Definition
Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).
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| - Definition
Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.
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| - Definition
Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.
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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.
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Reflects the sum of all other revenue and income recognized by the entity in the period not otherwise specified in the income statement.
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| - Definition
Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned.
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| - Definition
The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.
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| - Definition
Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
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