Fair Value of Assets and Liabilities - Change in unrealized gains and losses included in net income for level 3 assets and liabilities (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Gains (losses) included in net income for Level 3 assets and liabilities:
Recurring Level 3 assets	$ (29)	$ 4
Gains (losses) for Level 3 liabilities still held at the balance sheet date, included in earnings	48	(28)
Gains (losses) for Level 3 assets and liabilities still held at the balance sheet date, included in earnings	19	(24)
Changes in unrealized net capital gains and losses reported in OCI	(2)
Contractholder funds: Derivatives embedded in life and annuity contracts
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 liabilities still held at the balance sheet date, included in earnings	48	(28)
Municipal
Gains (losses) included in net income for Level 3 assets and liabilities:
Recurring Level 3 assets	1	0
Changes in unrealized net capital gains and losses reported in OCI	(1)
Equity securities
Gains (losses) included in net income for Level 3 assets and liabilities:
Recurring Level 3 assets	(30)	4
Free-standing derivatives, net
Gains (losses) included in net income for Level 3 assets and liabilities:
Recurring Level 3 assets	0	0
Corporate - privately placed
Gains (losses) included in net income for Level 3 assets and liabilities:
Changes in unrealized net capital gains and losses reported in OCI	(1)
Net Investment Income
Gains (losses) included in net income for Level 3 assets and liabilities:
Recurring Level 3 assets	(23)	0
Realized capital gains (losses)
Gains (losses) included in net income for Level 3 assets and liabilities:
Recurring Level 3 assets	(6)	4
Life contract benefits
Gains (losses) included in net income for Level 3 assets and liabilities:
Recurring Level 3 assets	(24)	8
Interest credited to contractholder funds
Gains (losses) included in net income for Level 3 assets and liabilities:
Recurring Level 3 assets	$ 72	$ (36)

This item represents the amount of the total change in unrealized (holding) gains or losses for the period which are included in the statement of income (or changes in net assets). Such unrealized (holding) gains or losses relate to those assets and liabilities still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

No definition available.

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- References

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- Definition

This item represents the amount of the total change in unrealized (holding) gains or losses for the period which are included in the statement of income (or changes in net assets). Such unrealized (holding) gains or losses relate to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

+ References

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- Definition

Amount of unrealized and realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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- Definition

Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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