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Fair Value Measurements - Impaired Loans Remeasured and Reported at Fair Value of Underlying Collateral (Detail) - USD ($) $ in Thousands | Sep. 30, 2016 | Dec. 31, 2015 | Sep. 30, 2015
--- | --- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Carrying value of impaired loans before allocations | $ 89,562 | $ 77,478 |
Specific valuation allowance allocations | (7,785) | $ (4,378) |
Level 2 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Carrying value of impaired loans before allocations | 0 |  | $ 130
Specific valuation allowance allocations | 0 |  | (71)
Loans receivable, fair value disclosure | 0 |  | 59
Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Carrying value of impaired loans before allocations | 11,023 |  | 959
Specific valuation allowance allocations | (3,750) |  |
Impaired Financing Receivable Related Allowance Reversal |  |  | 150
Loans receivable, fair value disclosure | $ 7,273 |  | $ 1,109

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- Definition Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 14A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524 + Details
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