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Fair Value Measurements (Impaired Loans Remeasured and Reported at Fair Value of Underlying Collateral) (Detail) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Carrying value of impaired loans before allocations |  | $ 99,453 |
Specific valuation allowance allocations |  | (28,483) |
Level 2 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Carrying value of impaired loans before allocations | $ 1,559 | 2,354 | $ 12,517
Specific valuation allowance allocations | (450) | (383) | (2,599)
Fair value | 1,109 | 1,971 | 9,918
Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Carrying value of impaired loans before allocations | 34,302 | 65,176 | 22,688
Specific valuation allowance allocations | (11,151) | (18,019) |
Reversal of specific valuation allowance allocations |  |  | 9,260
Fair value | $ 23,151 | $ 47,157 | $ 31,948

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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 14A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953550-111524 + Details
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