Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Cash Flows [Abstract]
Net cash provided by (used in) operating activities	$ 1,296	$ 2,098
Cash flows from investing activities
Sales, maturities and repayments of fixed maturity securities	26,053	23,086
Sales, maturities and repayments of equity securities	187	188
Sales, maturities and repayments of mortgage loans	2,076	1,776
Sales, maturities and repayments of real estate and real estate joint ventures	128	39
Sales, maturities and repayments of other limited partnership interests	139	461
Purchases of fixed maturity securities	(24,220)	(22,484)
Purchases of equity securities	(51)	(299)
Purchases of mortgage loans	(4,024)	(3,430)
Purchases of real estate and real estate joint ventures	(242)	(341)
Purchases of other limited partnership interests	(260)	(362)
Cash received in connection with freestanding derivatives	1,974	2,515
Cash paid in connection with freestanding derivatives	(2,192)	(3,372)
Net change in policy loans	(25)	(20)
Net change in short-term investments	(160)	(1,892)
Net change in other invested assets	46	(43)
Other, net	86	(98)
Net cash provided by (used in) investing activities	(485)	(4,276)
Cash flows from financing activities
Policyholder account balances: Deposits	24,861	21,271
Policyholder account balances: Withdrawals	(24,447)	(19,100)
Net change in payables for collateral under securities loaned and other transactions	667	391
Long-term debt issued	14	0
Long-term debt repaid	(32)	(4)
Collateral financing arrangements repaid	(13)	(12)
Financing element on certain derivative instruments and other derivative related transactions, net	37	188
Treasury stock acquired in connection with share repurchases	(1,041)	(858)
Preferred stock issued, net of issuance costs	494	0
Dividends on preferred stock	(6)	(6)
Dividends on common stock	(416)	(437)
Other, net	100	66
Net cash provided by (used in) financing activities	218	1,499
Effect of change in foreign currency exchange rates on cash and cash equivalents balances	197	213
Change in cash and cash equivalents	1,226	(466)
Cash and cash equivalents, beginning of period	12,701	17,877
Cash and cash equivalents, end of period	13,927	17,411
Cash and cash equivalents, of disposed subsidiary, beginning of period	0	5,226
Cash and cash equivalents, of disposed subsidiary, end of period	0	5,810
Cash and cash equivalents, from continuing operations, beginning of period	12,701	12,651
Cash and cash equivalents, from continuing operations, end of period	13,927	11,601
Supplemental disclosures of cash flow information:
Net cash paid for Interest	243	255
Net cash paid (received) for Income tax	$ 146	$ 109