Fair Value - Carrying Value and Fair Value Classified by Level (Details) - Nonrecurring - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Carrying Value
Assets:
Mortgage loans	$ 976	$ 1,047
Equity securities	129	145
Liabilities:
Investment contracts liabilities with a fixed maturity	5	5
Investment contracts liabilities without a fixed maturity	324	322
Long-term debt	59,354	64,647
Level 1 \| Estimated Fair Value
Assets:
Mortgage loans	0	0
Liabilities:
Investment contracts liabilities with a fixed maturity	0	0
Investment contracts liabilities without a fixed maturity	0	0
Long-term debt	68,364	75,940
Level 2 \| Estimated Fair Value
Assets:
Mortgage loans	0	0
Liabilities:
Investment contracts liabilities with a fixed maturity	0	0
Investment contracts liabilities without a fixed maturity	0	0
Long-term debt	0	0
Level 3 \| Estimated Fair Value
Assets:
Mortgage loans	992	1,070
Liabilities:
Investment contracts liabilities with a fixed maturity	5	5
Investment contracts liabilities without a fixed maturity	363	371
Long-term debt	0	0
Total \| Estimated Fair Value
Assets:
Mortgage loans	992	1,070
Liabilities:
Investment contracts liabilities with a fixed maturity	5	5
Investment contracts liabilities without a fixed maturity	363	371
Long-term debt	$ 68,364	$ 75,940

Investment Contracts With Fixed Maturity, Fair Value Disclosure.

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- Definition

Investment Contracts Without A Fixed Maturity, Fair Value Disclosure.

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

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Amount of investment in equity security without readily determinable fair value.

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Fair value portion of mortgage loans held-for-sale.

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