Schedule II. Condensed Financial Information of Registrant (Parent Company) (Schedule of Condensed Financial Information of Registrant, Statements of Cash Flows) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net income (loss)	$ 628	$ 612	$ 691
Adjustments to reconcile net income (loss) to net cash flows provided (used) by operating activities:
Other, net	14	10	5
Total adjustments	622	1,076	(758)
Net cash flows provided (used) by operating activities-total	1,250	1,702	(89)
Cash Flows from Investing Activities
Change in short term investments	(7)	566	1,629
Other, net	16	1	7
Net cash flows provided (used) by investing activities-total	(934)	(1,060)	767
Cash Flows from Financing Activities
Dividends paid to common stockholders	(162)	(108)
Dividends paid to Loews Corporation for 2008 Senior Preferred			(76)
Payment to redeem 2008 Senior Preferred			(1,000)
Proceeds from the issuance of debt		396	495
Repayment of debt	(70)	(451)	(150)
Stock options exercised	1	2	11
Other, net	(8)	(8)	(22)
Net cash flows provided (used) by financing activities-total	(239)	(644)	(742)
Net change in cash	81	(2)	(63)
Cash, beginning of year	75	77	140
Cash, end of year	156	75	77
Parent Company [Member]
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net income (loss)	628	612	691
Adjustments to reconcile net income (loss) to net cash flows provided (used) by operating activities:
Equity in net income of subsidiaries	(635)	(704)	(726)
Dividends received from subsidiaries	450	0	1
Net realized investment (gains) losses	(4)	9	1
Other, net	19	55	85
Total adjustments	(170)	(640)	(639)
Net cash flows provided (used) by operating activities-total	458	(28)	52
Cash Flows from Investing Activities
Proceeds from fixed maturity securities	1	1	(2)
Change in short term investments	(156)	(77)	181
Capital contributions to subsidiaries	(399)	(38)	(6)
Return of capital from subsidiaries		6
Repayment of surplus note by subsidiary	250	250	500
Other, net	4	1
Net cash flows provided (used) by investing activities-total	(300)	143	673
Cash Flows from Financing Activities
Dividends paid to common stockholders	(162)	(108)
Dividends paid to Loews Corporation for 2008 Senior Preferred			(76)
Payment to redeem 2008 Senior Preferred			(1,000)
Proceeds from the issuance of debt		396	495
Repayment of debt		(409)	(150)
Stock options exercised	1	5	3
Other, net	3	1	3
Net cash flows provided (used) by financing activities-total	(158)	(115)	(725)
Net change in cash
Cash, beginning of year
Cash, end of year