Summary of Significant Accounting Policies (Details) $ in Thousands	Jun. 30, 2020 USD ($) branch	Sep. 30, 2019 USD ($)
Accounting Policies [Line Items]
Number of bank branches \| branch	234
Cash collateral	$ 104,000	$ 31,850
Loans in process	1,353,774	1,201,341
Financing Receivable
Accounting Policies [Line Items]
Loans in process	$ 2,235,184	$ 2,379,089

Carrying amount as of the balance sheet date of cash collateral held for borrowed securities, for which the cash is restricted as to withdrawal or usage.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.1)
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.(a),2)
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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- Definition

Amount of undisbursed portion of financing receivable balance. Excludes financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5066-111524

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- Definition

Accounting Policies

+ References

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- Definition

Number of bank branches where the Bank conducts its activities

+ References

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