AOCI Rollforward (Details 2) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		$ 262	$ (291)
OCI before reclassifications		(563)	331
Amounts reclassified from AOCI		6	(5)
Total other comprehensive income (loss), net of tax		(557)	326
Ending balance		(295)	35
Accumulated Other Comprehensive Income (Loss) Available For Sale Securities Impairment Other than Credit		0	4
Net unrealized gains (losses) on securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		576	20
OCI before reclassifications		(530)	326
Amounts reclassified from AOCI		6	(4)
Total other comprehensive income (loss), net of tax		(524)	322
Ending balance	[1]	52	342
Net unrealized gains (losses) on derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		6	8
OCI before reclassifications		0	0
Amounts reclassified from AOCI		0	(1)
Total other comprehensive income (loss), net of tax		0	(1)
Ending balance		6	7
Defined benefit plans [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		(138)	(120)
OCI before reclassifications		0	0
Amounts reclassified from AOCI		0	0
Total other comprehensive income (loss), net of tax		0	0
Ending balance		(138)	(120)
Foreign currency translation [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		(181)	(198)
OCI before reclassifications		(33)	5
Amounts reclassified from AOCI		0	0
Total other comprehensive income (loss), net of tax		(33)	5
Ending balance		(214)	(193)
Other [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		(1)	(1)
OCI before reclassifications		0	0
Amounts reclassified from AOCI		0	0
Total other comprehensive income (loss), net of tax		0	0
Ending balance		$ (1)	$ (1)

[1] Includes nil and $(4) million of noncredit related impairments on securities and net unrealized gains (losses) on previously impaired securities as of March 31, 2020 and March 31, 2019, respectively.