Fair Value - Carrying Value and Fair Value Classified by Level (Details) - Nonrecurring - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Carrying Value
Assets:
Mortgage loans	$ 997	$ 1,047
Equity securities	194	145
Liabilities:
Investment contracts liabilities with a fixed maturity	5	5
Investment contracts liabilities without a fixed maturity	322	322
Long-term debt	61,692	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	68,890	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	1,011	1,070
Liabilities:
Investment contracts liabilities with a fixed maturity	5	5
Investment contracts liabilities without a fixed maturity	353	371
Long-term debt	0	0
Total \| Estimated Fair Value
Assets:
Mortgage loans	1,011	1,070
Liabilities:
Investment contracts liabilities with a fixed maturity	5	5
Investment contracts liabilities without a fixed maturity	353	371
Long-term debt	$ 68,890	$ 75,940

Investment Contracts With Fixed Maturity, Fair Value Disclosure.

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- Definition

Investment Contracts Without A Fixed Maturity, Fair Value Disclosure.

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117539-209714

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- Definition

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

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