| **Non-Insurance Revenues from Contracts with Customers** | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
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| **Revenue from Contract with Customer [Abstract]**       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| Non-Insurance Revenues from Contracts with Customers     | Non-Insurance Revenues from Contracts with CustomersThe Company reported $3.9 billion of Deferred non-insurance warranty revenue as of June 30, 2020 and $3.8 billion as of December 31, 2019.  For the three and six months ended June 30, 2020, the Company recognized $278 million and $564 million of revenues that were included in the deferred revenue balance as of January 1, 2020.  For the three and six months ended June 30, 2019, the Company recognized $246 million and $511 million of revenues that were included in the deferred revenue balance as of January 1, 2019.  For the three and six months ended June 30, 2020 and 2019, Non-insurance warranty revenue recognized from performance obligations related to prior periods due to a change in estimate was not material.  The Company expects to recognize approximately $0.6 billion of the deferred revenue in the remainder of 2020, $1.0 billion in 2021, $0.8 billion in 2022 and $1.5 billion thereafter. |

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No definition available.
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| - Definition
The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.
+ References
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