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Loans - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
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Dec. 31, 2012 | Dec. 31, 2011
Finance Receivable Transferred To Held For Sale [Line Items] |  |
Loans at Carrying Amount | $ 9,203 | $ 18,996
Loan impairments | 0 | 0
VIEs [Member] |  |
Finance Receivable Transferred To Held For Sale [Line Items] |  |
Loans at Carrying Amount | 209,807 | 202,696
Loans outstanding maturity date | 2047 | 2047
Loan impairments | $ 0 | $ 0
Minimum [Member] |  |
Finance Receivable Transferred To Held For Sale [Line Items] |  |
Interest rate on loans | 4.67% | 3.01%
Loans outstanding maturity date | 2013-12 | 2013-12
Minimum [Member] | VIEs [Member] |  |
Finance Receivable Transferred To Held For Sale [Line Items] |  |
Interest rate on loans | 5.33% | 5.33%
Maximum [Member] |  |
Finance Receivable Transferred To Held For Sale [Line Items] |  |
Interest rate on loans | 7.00% | 7.00%
Loans outstanding maturity date | 2026-06 | 2026-06
Maximum [Member] | VIEs [Member] |  |
Finance Receivable Transferred To Held For Sale [Line Items] |  |
Interest rate on loans | 5.42% | 5.42%

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- Details
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- Definition Interest Rate On Term Loan + References No definition available. + Details
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- Definition Loan Maturity date + References No definition available. + Details
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- Definition Maturity Year Of Long Term Debt + References No definition available. + Details
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- Definition Amount of allowance for credit losses related to recorded investment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5212-111524 + Details
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- Definition Total of loans held-for-sale and held-in-portfolio net of unearned income, allowance for loan and lease losses, if any, unamortized loan origination and other fees and costs, and purchased premiums or discounts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Subparagraph a -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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