Schedule II. Condensed Financial Information of Registrant (Parent Company) (Schedule of Condensed Financial Information of Registrant, Statements of Cash Flows) (Details) - USD ($) $ in Millions	3 Months Ended										12 Months Ended
	Dec. 31, 2015		Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014		Dec. 31, 2015		Dec. 31, 2014		Dec. 31, 2013
Cash Flows from Operating Activities
Net income (loss)	$ (70)	[1]	$ 178	$ 138	$ 233	$ 198	$ 213	$ 267	$ 13	[2]	$ 479	[1]	$ 691	[2]	$ 937
Adjustments to reconcile net income (loss) to net cash flows provided (used) by operating activities:
Net realized investment (gains) losses											67		(57)		(20)
Other, net											(2)		54		10
Total adjustments											908		749		267
Net cash flows provided (used) by operating activities											1,387		1,440		1,204
Cash Flows from Investing Activities
Change in short term investments											34		(388)		425
Other, net											21		16		11
Net cash flows provided (used) by investing activities											(372)		(918)		(898)
Cash Flows from Financing Activities
Dividends paid to common stockholders											(811)		(541)		(216)
Proceeds from the issuance of debt											0		546		0
Repayment of debt											0		(549)		(13)
Other, net											4		25		(35)
Net cash flows provided (used) by financing activities											(807)		(519)		(264)
Net change in cash											197		(5)		39
Cash, beginning of year					190				195		190		195		156
Cash, end of year	387					190					387		190		195
Parent Company [Member]
Cash Flows from Operating Activities
Net income (loss)											479		691		937
Adjustments to reconcile net income (loss) to net cash flows provided (used) by operating activities:
Equity in net income (loss) of subsidiaries											(594)		(838)		(1,068)
Dividends received from subsidiaries											900		650		400
Net realized investment (gains) losses											(5)		(4)		(4)
Other, net											4		14		8
Total adjustments											305		(178)		(664)
Net cash flows provided (used) by operating activities											784		513		273
Cash Flows from Investing Activities
Proceeds from fixed maturity securities											0		0		1
Change in short term investments											21		6		(57)
Capital contributions to subsidiaries											0		(10)		(12)
Other, net											7		5		4
Net cash flows provided (used) by investing activities											28		1		(64)
Cash Flows from Financing Activities
Dividends paid to common stockholders											(811)		(541)		(216)
Proceeds from the issuance of debt											0		546		0
Repayment of debt											0		(549)		(3)
Stock options exercised											1		5		2
Other, net											1		25		9
Net cash flows provided (used) by financing activities											(809)		(514)		(208)
Net change in cash											3		0		1
Cash, beginning of year					$ 1				$ 1		1		1		0
Cash, end of year	$ 4					$ 1					$ 4		$ 1		$ 1

[1] Net income in the fourth quarter of 2015 included a charge related to recognition of a premium deficiency in our long term care business.

[2] Net income in the first quarter of 2014 included the impairment loss on the sale of CAC.