Consolidated Statements Of Cash Flows (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash flows from operating activities:
Net income (loss)	$ (1,319)	$ 53	$ 634
Adjustments to reconcile net income (loss) to net cash used by operating activities:
Accrued investment income	34	1	102
Premiums receivable	209	259	349
Deferred acquisition costs	61	61	100
Unearned premium revenue	(624)	(635)	(906)
Prepaid reinsurance premiums	8	75	180
Reinsurance premiums payable	(8)	(39)	(191)
Loss and loss adjustment expense reserves	(293)	(81)	196
Reinsurance recoverable on paid and unpaid losses	(1)	(11)	115
Insurance loss recoverable	(514)	(769)	(1,987)
Payable to reinsurers on recoveries	8	(71)	126
Accrued interest payable	(11)	1	(3)
Accounts receivable	7	5	41
Accrued expenses	16	11	(109)
Deferred fee revenue	(2)	(1)	(34)
Current income taxes	86	501	(292)
Amortization of bond (premiums) discounts, net	(8)	(23)	(59)
Depreciation	7	8	9
Amortization of medium-term notes (premiums) discounts, net	(11)	(5)	(16)
Net investment losses related to other-than-temporary impairments	101	64	467
Realized (gains) losses and other settlements on insured derivatives		(607)
Unrealized (gains) losses on insured derivatives	441	607	(1,650)
Net (gains) losses on financial instruments at fair value and foreign exchange	46	(430)	(221)
Other net realized (gains) losses	(235)	47	101
Deferred income tax benefit	(935)	(221)	1,091
(Gains) losses on extinguishment of debt	(26)	(60)	(269)
Share-based compensation	13	2	6
Other operating	(26)	2	28
Total adjustments to net income (loss)	(1,657)	(1,309)	(2,826)
Net cash provided (used) by operating activities	(2,976)	(1,256)	(2,192)
Cash flows from investing activities:
Purchase of fixed-maturity securities	(7,744)	(9,967)	(10,422)
Sale and redemption of fixed-maturity securities	11,321	11,896	12,677
Decrease in loans receivable	291	860
Purchase of held-to-maturity investments		(157)	(251)
Redemptions of held-to-maturity investments	196	756	750
Sale (purchase) of short-term investments, net	680	662	2,011
Sale (purchase) of other investments, net	73	53	217
Purchase of controlling interest in an affiliate, net of cash received		(27)
Consolidation/deconsolidation of variable interest entities, net	(432)	754
(Payments) proceeds for derivative settlements	(85)	17
Collateral (to) from swap counterparty		166
Capital expenditures	(5)	(5)	(6)
Disposals of capital assets		3
Net cash provided (used) by investing activities	4,295	5,011	4,976
Cash flows from financing activities:
Proceeds from issuance of investment agreements	108	97	148
Payments for drawdowns of investment agreements	(524)	(767)	(2,047)
Issuance of medium-term notes	24	25	176
Principal paydown of medium-term notes	(137)	(507)	(2,345)
Principal paydown of variable interest entity notes	(1,100)	(1,793)	(128)
Securities sold under agreements to repurchase	(184)	(31)	(317)
Dividends paid		(1)	(10)
Net proceeds from issuance of debt	105		279
Payments for retirement of debt	(65)	(393)	(55)
Proceeds from bank loans			88
(Payments) proceeds for derivative settlements			46
Purchase of treasury stock	(50)	(31)	(16)
Contribution from noncontrolling interest and redemption of subsidiary preferred stock, net	9	(29)	(11)
Restricted stock awards settlements	(2)	2	2
Collateral from reverse repurchase agreement counterparties			30
Collateral (to) from swap counterparty			(101)
Net cash provided (used) by financing activities	(1,816)	(3,428)	(4,261)
Net increase (decrease) in cash and cash equivalents	(497)	327	(1,477)
Cash and cash equivalents - beginning of period	1,130	803	2,280
Cash and cash equivalents - end of period	633	1,130	803
Supplemental cash flow disclosures:
Income taxes refunded	(74)	(414)	(209)
Interest paid:
Investment agreements	33	92	133
Medium-term notes	36	64	96
Variable interest entity notes	273	290	105
Securities sold under agreements to repurchase	1	2	72
Other borrowings and deposits	4	7	8
Long-term debt	193	199	204
Noncash items:
Share-based compensation	13	2	6
Dividends declared but not paid			$ 1