Condensed Consolidated Statements Of Cash Flows (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Cash flows from operating activities
Net income	$ 1,115	$ 254
Adjustments to reconcile net income to net cash provided by operating activities:
Net realized capital gains	(26)	(20)
Stock-based compensation	26	23
Depreciation	100	94
Other intangible amortization	18	21
Provision for deferred income taxes	29	15
Changes in operating assets and liabilities, net of effect of businesses acquired and dispositions:
Receivables	(558)	(576)
Other assets	(415)	(685)
Benefits payable	198	138
Other liabilities	542	1,210
Unearned revenues	3,140	(4)
Other, net	36	32
Net cash provided by operating activities	4,205	502
Cash flows from investing activities
Acquisitions, net of cash acquired	(7)	0
Purchases of property and equipment	(122)	(125)
Purchases of investment securities	(1,876)	(1,430)
Maturities of investment securities	284	213
Proceeds from sales of investment securities	795	914
Net cash used in investing activities	(926)	(428)
Cash flows from financing activities
Receipts from contract deposits, net	1,730	318
Proceeds from issuance of senior notes, net	991	0
Proceeds from issuance of commercial paper, net	169	0
Change in book overdraft	(34)	(44)
Common stock repurchases	(1,574)	(71)
Dividends paid	(47)	(47)
Proceeds from stock option exercises and other	34	0
Net cash provided by financing activities	1,269	156
Increase in cash and cash equivalents	4,548	230
Cash and cash equivalents at beginning of period	3,877	2,571
Cash and cash equivalents at end of period	8,425	2,801
Supplemental cash flow disclosures:
Interest payments	10	10
Income tax (refunds) payments, net	$ (4)	$ 5