Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Unrealized holding loss on investment securities available for sale, tax	$ 2	$ (1)	$ 15	$ (5)
Adjustments related to other factors for which OTTI was previously recognized, tax	(1)	0	(2)	(2)
Amount reclassified to credit loss for previously recorded market loss, tax	0	0	2	1
Accretion of OTTI on investment securities held to maturity, tax	$ 2	$ 2	$ 5	$ 8

Amount of tax (expense) benefit of other than temporary impairment (OTTI) on investment in held-to-maturity debt security, recognized in other comprehensive loss, attributable to the parent entity.

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