Schedule II - (Notes to Condensed Financial Statements) (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Fair value of securities pledged as collateral	$ 314	$ 353
Securities posted as collateral to derivative counterparties	$ 205	237
MBIA Inc. Senior Notes [Member]
Long-term debt, interest rate	5.70%
Long-term debt, maturity year	2034
Mbia Inc. Debentures [Member]
Long-term debt, interest rate	7.00%
Long-term debt, maturity year	2025
National Public Finance Guarantee Holdings, Inc. [Member]
Dividends from subsidiaries	$ 1	118	$ 118
MBIA Inc. [Member]
Liquid assets	457
Fair value of securities pledged as collateral	314	350
Securities posted as collateral to derivative counterparties	205	237
National [Member]
Dividends from subsidiaries	108	118
National [Member] \| MBIA Inc. Senior Notes [Member]
Long-term debt principal amount purchased	44	$ 129
National [Member] \| Mbia Inc. Debentures [Member]
Long-term debt principal amount purchased	10
MBIA Capital Corp. [Member]
Dividends from subsidiaries	$ 3

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This element represents disclosure of the aggregate cash dividends paid to the entity by consolidated subsidiaries.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Face (par) amount of the original debt instrument that was repurchased.

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Amount of right to receive securities collateral under master netting arrangements that have not been offset against derivative liabilities.

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- Definition

Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions.

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