Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 222	$ 1,183	$ 4,021	$ 3,873
Other comprehensive income, net of tax:
Change in net unrealized losses/gains on investments	113	116	154	711
Change in non-credit component of impairment losses on investments	16	(1)	(6)	(2)
Change in net unrealized gains/losses on cash flow hedges	4	(34)	10	(31)
Change in net periodic pension and postretirement costs	8	4	25	10
Foreign currency translation adjustments	1	(1)	1	(1)
Other comprehensive income	142	84	184	687
Total comprehensive income	$ 364	$ 1,267	$ 4,205	$ 4,560

Change in non-credit component of impairment losses on investments, net of tax effect.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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