CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS EQUITY (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Stockholders' Equity [Abstract]
Dividend declared per share (in dollars per share)	$ 0.10	$ 0.10	$ 0.30	$ 0.30
Changes in unrealized gains (losses) on marketable securities, tax				$ 0
Actuarial losses, tax	$ 3	$ 2	$ 4	$ 4

Aggregate dividends declared during the period for each share of common stock outstanding.

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Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

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Amount, before adjustment, of tax expense (benefit) for unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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