Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2017	Feb. 22, 2018	Jun. 30, 2017
Document Document and Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q4
Trading Symbol	MBI
Entity Registrant Name	MBIA INC
Entity Central Index Key	0000814585
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		88,763,473
Entity Well-Known Seasoned Issuer	Yes
Entity Public Float			$ 1,141,143,207
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No