Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Assets
Cash and cash equivalents	$ 782	$ 1,258
Premiums receivable	875	1,051
Assets held for sale	802	29
Net deferred tax asset	1,009	1,109
Investments held-to-maturity, at amortized cost (fair value $2,632 and $2,651)	2,757	2,801
Total assets	16,284	16,953
Liabilities:
Long-term debt	1,810	1,702
Derivative liabilities	246	1,200
Liabilities held for sale	772	0
Total liabilities	12,334	13,654
Commitments and contingencies (See Note 21)
Equity:
Preferred stock, par value $1 per share; authorized shares--10,000,000; issued and outstanding--none	0	0
Common stock, par value $1 per share; authorized shares--400,000,000; issued shares--281,352,782 and 277,812,430	281	278
Additional paid-in capital	3,128	3,115
Retained earnings	2,858	2,289
Accumulated other comprehensive income (loss), net of tax of $7 and $54	21	(86)
Treasury stock, at cost--89,409,887 and 85,562,546 shares	(2,359)	(2,318)
Total shareholders' equity of MBIA Inc.	3,929	3,278
Preferred stock of subsidiary and noncontrolling interest	21	21
Total equity	3,950	3,299
Total liabilities and equity	16,284	16,953
Non Variable Interest Entity [Member]
Assets
Fixed-maturity securities held as available-for-sale, at fair value (amortized cost $5,036 and $5,064) Investments held as available-for-sale, at fair value (amortized cost $0 and $136)	5,129	4,987
Investments carried at fair value	207	204
Investments pledged as collateral, at fair value (amortized cost $441 and $483)	408	424
Short-term investments held as available-for-sale, at fair value (amortized cost $1,069 and $1,203)	1,069	1,204
Other investments (includes investments at fair value of $13 and $11)	17	16
Total investments	6,830	6,835
Cash and cash equivalents	729	1,161
Premiums receivable	875	1,051
Deferred acquisition costs	217	260
Insurance loss recoverable	533	694
Net deferred tax asset	1,028
Deferred income taxes, net		1,109
Other assets	229	222
Liabilities:
Unearned premium revenue	1,986	2,441
Loss and loss adjustment expense reserves	506	641
Investment agreements	547	700
Medium-term notes (includes financial instruments carried at fair value of $197 and $203)	1,201	1,427
Long-term debt	1,810	1,702
Derivative liabilities	437	1,152
Other liabilities	271	294
Variable Interest Entity Primary Beneficiary [Member]
Assets
Fixed-maturity securities held as available-for-sale, at fair value (amortized cost $5,036 and $5,064) Investments held as available-for-sale, at fair value (amortized cost $0 and $136)	0	136
Investments carried at fair value	421	587
Cash	53	97
Investments held-to-maturity, at amortized cost (fair value $2,632 and $2,651)	2,757	2,801
Loans receivable at fair value	1,431	1,612
Loan repurchase commitments	379	359
Liabilities:
Derivative liabilities	0	11
Variable interest entity notes (includes financial instruments carried at fair value of $2,047 and $2,356)	4,804	5,286
Payable for loans purchased	$ 0	$ 0