Consolidated Statements Of Cash Flows (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Cash flows from operating activities:
Premiums, fees and reimbursements received	$ 72	$ 107
Investment income received	214	223
Insured derivative commutations and losses paid	(371)	(419)
Financial guarantee losses and loss adjustment expenses paid	(139)	(227)
Proceeds from recoveries and reinsurance	60	1,781
Operating and employee related expenses paid	(142)	(176)
Interest paid, net of interest converted to principal	(95)	(118)
Income taxes (paid) received	5	0
Net cash provided (used) by operating activities	(396)	1,171
Cash flows from investing activities:
Purchases of available-for-sale investments	(975)	(928)
Sales of available-for-sale investments	463	1,301
Paydowns and maturities of available-for-sale investments	255	377
Purchases of investments at fair value	(259)	(245)
Sales, paydowns and maturities of investments at fair value	343	338
Sales, paydowns and maturities (purchases) of short-term investments, net	309	(1,242)
Sales, paydowns and maturities of held-to-maturity investments	14	12
Paydowns and maturities of loans	112	137
Consolidation (deconsolidation) of variable interest entities, net	(1)	(26)
(Payments) proceeds for derivative settlements	(15)	(39)
Collateral (to) from swap counterparty	81	63
Capital expenditures	(3)	(1)
Net cash provided (used) by investing activities	324	(253)
Cash flows from financing activities:
Proceeds from investment agreements	11	15
Principal paydowns of investment agreements	(57)	(190)
Principal paydowns of medium-term notes	(166)	(40)
Principal paydowns of variable interest entity notes	(377)	(685)
Payments for retirement of debt	0	(2)
Net cash provided (used) by financing activities	(589)	(902)
Effect of exchange rate changes on cash and cash equivalents	3	0
Net increase (decrease) in cash and cash equivalents	(658)	16
Cash and cash equivalents - beginning of period	1,258	990
Cash and cash equivalents - end of period	600	1,006
Reconciliation of net income (loss) to net cash provided (used) by operating activities: [Abstract]
Net income (loss)	376	(14)
Change in: [Abstract]
Premiums receivable	83	91
Deferred acquisition costs	17	24
Unearned premium revenue	(204)	(265)
Loss and loss adjustment expense reserves	(87)	(79)
Insurance loss recoverable	70	2,754
Accrued interest payable	51	56
Accrued expenses	(27)	39
Realized (gains) losses and other settlements on insured derivatives	30	0
Unrealized (gains) losses on insured derivatives	(815)	(1,277)
Net (gains) losses on financial instruments at fair value and foreign exchange	(32)	(168)
Deferred income tax provision (benefit)	76	(37)
(Gains) losses on extinguishment of debt	(7)	(43)
Interest on variable interest entities, net	37	49
Other operating	36	41
Total adjustments to net income (loss)	(772)	1,185
Net cash provided (used) by operating activities	$ (396)	$ 1,171