Consolidated Statements Of Changes In Shareholders' Equity - USD ($) $ in Millions	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings (deficit) [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Total Shareholders' Equity Of MBIA Inc. [Member]	Preferred Stock [Member]
Total equity balance at Dec. 31, 2020			$ 2,962	$ (13)	$ 115	$ (3,211)	$ 136
Balance (in treasury stock shares) at Dec. 31, 2020						(229,508,967)
Net income (loss)	$ (167)			(167)
Other comprehensive income (loss)	(12)				(12)
Other						$ 35
Others (in shares)						728,427
Period change			(28)				(172)
Total equity balance at Jun. 30, 2021	(23)	$ 283	2,934	(180)	103	$ (3,176)	(36)	$ 13
Balance (in common stock shares) at Jun. 30, 2021		283,186,115
Balance (in treasury stock shares) at Jun. 30, 2021						(228,780,540)
Balance (in preferred stock shares) at Jun. 30, 2021								1,315
Total equity balance at Mar. 31, 2021			2,934	(119)	39	$ (3,179)	(42)
Balance (in treasury stock shares) at Mar. 31, 2021						(228,837,465)
Net income (loss)	(61)			(61)
Other comprehensive income (loss)	64				64
Other						$ 3
Others (in shares)						56,925
Period change			0				6
Total equity balance at Jun. 30, 2021	(23)	$ 283	2,934	(180)	103	$ (3,176)	(36)	$ 13
Balance (in common stock shares) at Jun. 30, 2021		283,186,115
Balance (in treasury stock shares) at Jun. 30, 2021						(228,780,540)
Balance (in preferred stock shares) at Jun. 30, 2021								1,315
Total equity balance at Dec. 31, 2021	$ (300)		2,931	(458)	100	$ (3,169)	(313)
Balance (in treasury stock shares) at Dec. 31, 2021	(228,630,003)					(228,630,003)
Net income (loss)	$ (109)			(109)
Other comprehensive income (loss)	(331)				(331)
Other						$ 17
Others (in shares)						343,604
Period change			(12)				(435)
Total equity balance at Jun. 30, 2022	$ (735)	$ 283	2,919	(567)	(231)	$ (3,152)	(748)	$ 13
Balance (in common stock shares) at Jun. 30, 2022	283,186,115	283,186,115
Balance (in treasury stock shares) at Jun. 30, 2022	(228,286,399)					(228,286,399)
Balance (in preferred stock shares) at Jun. 30, 2022	0							1,315
Total equity balance at Mar. 31, 2022			2,919	(531)	(82)	$ (3,154)	(565)
Balance (in treasury stock shares) at Mar. 31, 2022						(228,329,115)
Net income (loss)	$ (36)			(36)
Other comprehensive income (loss)	(149)				(149)
Other						$ 2
Others (in shares)						42,716
Period change			0				(183)
Total equity balance at Jun. 30, 2022	$ (735)	$ 283	$ 2,919	$ (567)	$ (231)	$ (3,152)	$ (748)	$ 13
Balance (in common stock shares) at Jun. 30, 2022	283,186,115	283,186,115
Balance (in treasury stock shares) at Jun. 30, 2022	(228,286,399)					(228,286,399)
Balance (in preferred stock shares) at Jun. 30, 2022	0							1,315