SECURITIES - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Sep. 30, 2018
Item Effected [Line Items]
Equity securities cost	$ 1,800
Equity securities fair value	1,800
Equity Securities without readily determinable fair value, amount	2,000	$ 2,000
Federal Home Loan Bank Stock, at cost	15,600	23,400
Mortgage-backed securities available for sale, at fair value	$ 354,186	364,065
Accounting Standards Update 2016-01 [Member] \| Retained Earnings [Member]
Item Effected [Line Items]
Cumulative Effect of New Accounting Principle in Period of Adoption		$ 475

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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