Fair Value of Assets and Liabilities - Rollforward of level 3 assets and liabilities held at fair value on a recurring basis during the period (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Assets
Balance at beginning of period	$ 565	$ 832
Total gains (losses) included in: net income	38	18
Total gains (losses) included in: OCI	(1)	(4)
Transfers into Level 3	0	13
Transfers out of Level 3	(28)	(47)
Transfers to (from) held for sale		0
Purchases	113	125
Sales	(7)	(47)
Issues	0	0
Settlements	(2)	(39)
Balance at end of period	678	851
Liabilities
Balance at the beginning of the period	0	(516)
Total gains (losses) included in: net income	0	55
Total gains (losses) included in: OCI	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Transfers to (from) held for sale		0
Purchases	0	0
Sales	0	0
Issues	0	(8)
Settlements	0	6
Balance at the end of the period	0	(463)
Net investment income
Total Level 3 gains (losses) included in net income
Gain (loss) included in earnings	9	(1)
Net gains (losses) on investments and derivatives
Total Level 3 gains (losses) included in net income
Gain (loss) included in earnings	29	18
Liabilities held for sale
Liabilities
Balance at the beginning of the period		(516)
Total gains (losses) included in: net income	0	55
Total gains (losses) included in: OCI		0
Transfers into Level 3		0
Transfers out of Level 3		0
Transfers to (from) held for sale		0
Purchases		0
Sales		0
Issues		(8)
Settlements		6
Balance at the end of the period		(463)
Municipal
Assets
Balance at beginning of period	18	17
Total gains (losses) included in: net income	0	0
Total gains (losses) included in: OCI	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Transfers to (from) held for sale		0
Purchases	0	3
Sales	0	0
Issues	0	0
Settlements	(1)	(2)
Balance at end of period	17	18
Corporate - public
Assets
Balance at beginning of period	20	67
Total gains (losses) included in: net income	0	1
Total gains (losses) included in: OCI	(2)	(3)
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Transfers to (from) held for sale		(6)
Purchases	35	17
Sales	(4)	(33)
Issues	0	0
Settlements	0	0
Balance at end of period	49	43
Corporate - privately placed
Assets
Balance at beginning of period	66	63
Total gains (losses) included in: net income	0	0
Total gains (losses) included in: OCI	1	(1)
Transfers into Level 3	0	10
Transfers out of Level 3	0	(7)
Transfers to (from) held for sale		13
Purchases	63	27
Sales	0	0
Issues	0	0
Settlements	0	0
Balance at end of period	130	105
ABS
Assets
Balance at beginning of period	40	79
Total gains (losses) included in: net income	1	0
Total gains (losses) included in: OCI	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	(28)	(32)
Transfers to (from) held for sale		0
Purchases	7	59
Sales	0	(4)
Issues	0	0
Settlements	(1)	0
Balance at end of period	19	102
Fixed income securities
Assets
Balance at beginning of period	144	226
Total gains (losses) included in: net income	1	1
Total gains (losses) included in: OCI	(1)	(4)
Transfers into Level 3	0	10
Transfers out of Level 3	(28)	(39)
Transfers to (from) held for sale		7
Purchases	105	106
Sales	(4)	(37)
Issues	0	0
Settlements	(2)	(2)
Balance at end of period	215	268
Equity securities
Assets
Balance at beginning of period	349	304
Total gains (losses) included in: net income	25	16
Total gains (losses) included in: OCI	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Transfers to (from) held for sale		92
Purchases	2	5
Sales	(3)	(7)
Issues	0	0
Settlements	0	0
Balance at end of period	373	410
Short-term investments
Assets
Balance at beginning of period	5	35
Total gains (losses) included in: net income	0	0
Total gains (losses) included in: OCI	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Transfers to (from) held for sale		0
Purchases	6	0
Sales	0	0
Issues	0	0
Settlements	0	(35)
Balance at end of period	11	0
Other investments
Assets
Balance at beginning of period	2	0
Total gains (losses) included in: net income	0	0
Total gains (losses) included in: OCI	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Transfers to (from) held for sale		0
Purchases	0	3
Sales	0	0
Issues	0	0
Settlements	0	0
Balance at end of period	2	3
Other assets
Assets
Balance at beginning of period	65
Total gains (losses) included in: net income	12
Total gains (losses) included in: OCI	0
Transfers into Level 3	0
Transfers out of Level 3	0
Purchases	0
Sales	0
Issues	0
Settlements	0
Balance at end of period	$ 77
Assets held for sale
Assets
Balance at beginning of period		267
Total gains (losses) included in: net income		1
Total gains (losses) included in: OCI		0
Transfers into Level 3		3
Transfers out of Level 3		(8)
Transfers to (from) held for sale		(99)
Purchases		11
Sales		(3)
Issues		0
Settlements		(2)
Balance at end of period		$ 170

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

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

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