Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net earnings	$ 23,849	$ 21,557	$ 32,229
Other comprehensive income (loss):
Foreign currency translation adjustment	(1,075)	1,616	(2,732)
Unrealized gain (loss) on cash flow hedge	907	1,544	(729)
Income taxes related to items of other comprehensive income	(263)	(590)	275
Other comprehensive income (loss), net of tax	(431)	2,570	(3,186)
Comprehensive Income	$ 23,418	$ 24,127	$ 29,043

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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