Reinsurance and Other Monoline Exposures - Reinsurer Exposure (Details) (USD $)	Mar. 31, 2014		Mar. 31, 2014 National Public Finance Guarantee Corporation	Mar. 31, 2014 American Overseas Reinsurance Company Limited (f/k/a Ram Re)		Mar. 31, 2014 Tokio Marine & Nichido Fire Insurance Co., Ltd.		Mar. 31, 2014 Radian Asset Assurance Inc.		Mar. 31, 2014 Syncora Guarantee Inc.		Mar. 31, 2014 Mitsui Sumitomo Insurance Co. Ltd.		Mar. 31, 2014 ACA Financial Guaranty Corp.		Mar. 31, 2014 Federal Insurance Company [Member]		Mar. 31, 2014 Swiss Reinsurance Co.		Mar. 31, 2014 Security Life of Denver Insurance Co [Member]		Mar. 31, 2014 Ambac (4)		Mar. 31, 2014 CIFG Assurance North America Inc.		Mar. 31, 2014 MBIA Inc.		Mar. 31, 2014 Financial Guaranty Insurance Co.		Mar. 31, 2014 Other		Mar. 31, 2014 AGM, AGC and MAC [Member]	Jan. 22, 2012 AGM and AGC
Exposure, Premium Receivable, and Loss and LAE by Reinsurer
Fixed maturity securities wrapped by monoline reinsurer			$ 435,000,000																			$ 455,000,000								$ 29,000,000
Ceded Par Amount	27,526,000,000	[1]		8,113,000,000	[1],[2]	6,273,000,000	[1]	4,696,000,000	[1]	4,192,000,000	[1]	2,139,000,000	[1],[3]	809,000,000	[1]	382,000,000	[1]	347,000,000	[1]	239,000,000	[1]	85,000,000	[1]	0	[1]	0	[1],[4]	0	[1]	251,000,000	[1]
Ceded Par Outstanding	22,518,000,000			0	[2]	0		24,000,000		1,769,000,000		0	[3]	3,000,000		0		0		0		6,013,000,000		114,000,000		10,208,000,000	[4]	2,273,000,000		2,114,000,000
Assumed Par Outstanding	32,150,000,000			30,000,000	[2]	0		987,000,000		161,000,000		0	[3]	8,000,000		0		0		0		17,578,000,000		4,883,000,000		7,221,000,000	[4]	1,237,000,000		45,000,000
Ceded par outstanding related to insured credit derivatives	3,038,000,000
Assumed Premium Receivable, net of Commissions	85,000,000			0		0		0		0		0				0		0		0		66,000,000		0		13,000,000		6,000,000		0
Ceded Premium Payable, net of Commissions	(141,000,000)			(9,000,000)		(18,000,000)		(17,000,000)		(39,000,000)		(3,000,000)				(17,000,000)		(3,000,000)		(10,000,000)		0		0		0		0		(25,000,000)
Assumed Expected Loss and LAE	(202,000,000)			0		0		0		0		0				0		0		0		(82,000,000)		(6,000,000)		(10,000,000)		(104,000,000)		0
Ceded Expected Loss and LAE	44,000,000			7,000,000		18,000,000		14,000,000		1,000,000		3,000,000				0		1,000,000		0		0		0		0		0		0
Minimum Net Losses Required for Attachment of Excess of Loss Reinsurance Facility																																1,500,000,000
Losses Above Minimum Net Loss Limit Covered under Excess of Loss Reinsurance Facility																																500,000,000
Losses Assumed by Reinsurers under Excess of Loss Reinsurance Facility																																450,000,000	435,000,000
Losses Above Remaining Net Loss Limit Covered under Excess of Loss Reinsurance Facility																																50,000,000
Insurance Premium Paid																																19,000,000
Remaining Insurance Premiums Payable																																$ 19,000,000

[1] Includes $3,038 million in ceded par outstanding related to insured credit derivatives.

[2] Represents “Withdrawn Rating.”

[3] The Company has structural collateral agreements satisfying the triple-A credit requirement of S&P and/or Moody’s.

[4] MBIA Inc. includes various subsidiaries which are rated AA- and B by S&P and Baa1, B1 and B3 by Moody’s.