Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Dec. 31, 2011		Dec. 31, 2010
Assets
Cash and cash equivalents	$ 633		$ 1,130
Total assets	26,873		32,279
Liabilities:
Unearned premium revenue
Total liabilities	25,150		29,433
Commitments and contingencies (See Note 23)
Equity:
Preferred stock, par value $1 per share; authorized shares - 10,000,000; issued and outstanding - none
Common stock, par value $1 per share; authorized shares - 400,000,000; issued shares - 274,896,162 and 274,719,578	275		275
Additional paid-in capital	3,072		3,064
Retained earnings	805		2,124
Accumulated other comprehensive loss, net of deferred tax of $105 and $229	(176)		(406)
Treasury stock, at cost-81,752,966 and 74,973,978 shares	(2,276)		(2,225)
Total shareholders' equity of MBIA Inc.	1,700		2,832
Preferred stock of subsidiary and noncontrolling interest	23		14
Total equity	1,723		2,846
Total liabilities and equity	26,873		32,279
Non Variable Interest Entities [Member]
Assets
Fixed-maturity securities held as available-for-sale, at fair value	6,177		9,092
Fixed-maturity securities at fair value	295		25
Investments pledged as collateral, at fair value (amortized cost $642 and $548)	543		552
Short-term investments held as available-for-sale, at fair value (amortized cost $1,577 and $2,073)	1,571		2,070
Other investments (includes investments at fair value of $96 and $185)	107		188
Total	8,693		11,927
Cash and cash equivalents	473		366
Accrued investment income	63		95
Premiums receivable	1,360		1,589
Deferred acquisition costs	351		412
Prepaid reinsurance premiums	88		97
Insurance loss recoverable	3,046		2,531
Reinsurance recoverable on paid and unpaid losses	16		15
Goodwill			31
Property and equipment, at cost (less accumulated depreciation of $139 and $135)	69		71
Receivable for investments sold	32		8
Derivative assets	2		4
Current income taxes			41
Deferred income taxes, net	1,745		908
Other assets	42		46
Liabilities:
Unearned premium revenue	3,515		4,145
Loss and loss adjustment expense reserves	836		1,129
Reinsurance premiums payable	64		71
Investment agreements	1,578		2,005
Medium-term notes (includes financial instruments carried at fair value $165 and $116)	1,656		1,740
Securities sold under agreements to repurchase	287		471
Short-term debt			65
Long-term debt	1,840		1,851
Current income taxes	48
Deferred fee revenue	8		10
Payable for investments purchased	3		2
Derivative liabilities	5,164		4,617
Other liabilities	268		272
Variable Interest Entities [Member]
Assets
Fixed-maturity securities held as available-for-sale, at fair value	432		339
Fixed-maturity securities at fair value	2,884		5,241
Derivative assets	450		699
Other assets	1		38
Cash	160		764
Investments held-to-maturity, at amortized cost (fair value $3,489 and $3,760)	3,843		4,039
Loans receivable at fair value	2,046		2,183
Loan repurchase commitments	1,077		835
Total assets	10,900		14,100
Liabilities:
Long-term debt	360		360
Derivative liabilities	825		2,104
Other liabilities	1		1
Variable interest entity notes (includes financial instruments carried at fair value $4,754 and $6,680)	8,697	[1]	10,590
Total liabilities	$ 9,900		$ 13,100

[1] Includes $4.8 billion of VIE notes accounted for at fair value as of December 31, 2011.