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Loans Receivable - Loan Modifications (Details) $ in Thousands	3 Months Ended
	Dec. 31, 2018 USD ($) contract	Dec. 31, 2017 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	1	1
Recorded Investment | $	$ 543	$ 44
Single-family residential
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	1	1
Recorded Investment | $	$ 543	$ 44

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- Definition

Financing Receivable, Modifications, Number of Contracts that Subsequently Defaulted

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- Definition

Financing Receivable, Modifications, Recorded Investment During the Period

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