CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Net income	$ 110,043	$ 86,952	$ 59,849
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	679	(6,746)	15,996
Minimum pension liability adjustment	(26)	276	(434)
Net unrealized gain (loss) on cash flow hedges	(63)	863	84
Other comprehensive income (loss), net of tax	590	(5,607)	15,646
Comprehensive income	$ 110,633	$ 81,345	$ 75,495

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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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity.

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