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Loans Receivable - Loans Impaired, Loan Commitments and Loans Serviced (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2017 | Sep. 30, 2016
Receivables [Abstract] |  |
Recorded investment in impaired loans | $ 251,274 | $ 285,243
TDRs included in impaired loans | 207,377 | 261,531
Allocated reserves on impaired loans | 1,363 | 1,980
Specific reserves on impaired loans | 126 | 366
Average balance of impaired loans for year ended | 274,530 | 301,685
Interest income from impaired loans for year ended | 11,736 | 12,843
Outstanding fixed-rate origination commitments | 425,130 | 331,947
Gross loans serviced for others | $ 77,119 | $ 80,896

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- Definition Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 + Details
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- Definition Reflects the amount of the write-down related to a troubled debt restructuring. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554 + Details
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- Definition Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired. + 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 (c)(2) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524 + Details
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- References No definition available. + Details
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- Definition Allocated Reserves on Impaired Loans + References No definition available. + Details
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- Definition Financing Receivable, Average Balance of Impaired Loans + References No definition available. + Details
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- Definition Loans and Leases Receivable, Loan Origination Commitments Outstanding + References No definition available. + Details
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- Definition Loans Serviced for Others + References No definition available. + Details
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- Definition Recorded investment in impaired loans + References No definition available. + Details
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