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Fair Value Measurements - Impaired Loans Remeasured and Reported at Fair Value of Underlying Collateral (Detail) - USD ($) $ in Thousands | Sep. 30, 2020 | Sep. 30, 2019
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Level 2 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Carrying value of impaired loans before allocations | $ 6,388 | $ 2,416
Impaired Financing Receivable Related Allowance Reversal |  | 1,116
Specific (allocations) reversals of prior allocations | (930) |
Loans receivable, fair value disclosure | 5,458 | 3,532
Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Carrying value of impaired loans before allocations | 8,660 | 60,010
Impaired Financing Receivable Related Allowance Reversal | 14,928 |
Specific (allocations) reversals of prior allocations |  | (12,437)
Loans receivable, fair value disclosure | $ 23,588 | $ 47,573

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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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- Definition Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -URI http://asc.fasb.org/subtopic&trid=2196772 + Details
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