CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (Parenthetical) - USD ($) $ in Thousands	6 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement of Stockholders' Equity [Abstract]
Dividend declared per share (in dollars per share)	$ 0.20	$ 0.20
Changes in unrealized gains (losses) on marketable securities, tax	$ 0
Actuarial gain or loss arising in the year, tax	$ 3	$ (2)

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 of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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