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Financial Guarantees in Force - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified |  |  | 12 Months Ended
--- | --- | --- | ---
Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2012 California [Member] | Dec. 31, 2012 New York [Member] | Dec. 31, 2012 Florida [Member] | Dec. 31, 2012 No other state [Member] Maximum [Member]
Guarantor Obligations [Line Items] |  |  |  |  |  |
Gross par amount of financial guarantees outstanding | $ 245,030,000 | $ 296,463,000 |  |  |  |
Net par amount of financial guarantees | 223,633,000 | 272,504,000 |  |  |  |
Gross financial guarantees in force | 385,803,000 | 474,305,000 |  |  |  |
Net financial guarantees in force | $ 350,163,000 | $ 433,484,000 |  |  |  |
Aggregate net par amounts in force |  |  | 14.40% | 6.40% | 5.00% | 5.00%
Highest single insured risk of aggregate net par amount guaranteed | 1.30% |  |  |  |  |

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- Definition Financial guarantee insurance gross outstanding principal and interest. + References No definition available. + Details
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- Definition Financial guarantee insurance outstanding principal and interest, net of reinsurance. + References No definition available. + Details
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- Definition Percentage of related member outstanding par, net of reinsurance, as compared to the Company's total outstanding financial guarantee par, net of reinsurance. + References No definition available. + Details
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- Definition Percentage of highest single insured risk of aggregate net par amount guaranteed + References No definition available. + Details
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- Details
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- Definition The amount as of the balance sheet date of the participating business in force. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 50 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6483535&loc=d3e16392-158451 + Details
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