INVESTMENT SECURITIES - Gross Realized Gain and Losses on Sales of Available for Sale Securities (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Gross Realized Gain and Losses
Gross realized gains on sales	$ 0	$ 17	$ 68
Gross realized losses on sales	0	(10)	(142)
Net realized gain (loss) on sales of available for sale securities and time deposits	$ 0	$ 7	$ (74)

Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and time deposits.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration