Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Income Taxes
Statutory federal tax rate (as a percent)	21.00%	21.00%	21.00%	21.00%
Effective tax rate (as a percent)	26.00%	26.00%	26.00%	128.10%
Income (loss) before income taxes	$ 5,497	$ 2,039	$ 9,914	$ 335
Increase in tax expense attributable to expiration of stock option grants			$ 300

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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