Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net earnings	$ 58,226	$ 66,539	$ 202,861	$ 179,357
Other comprehensive income (loss):
Foreign currency translation adjustments	(22,168)	17,686	(11,986)	7,044
Interest rate caps:
Changes in fair value	434		2,555
Income taxes related to changes in fair value	(126)		(740)
Other comprehensive income (loss), net of tax	(21,860)	17,686	(10,171)	7,044
Total comprehensive income	$ 36,366	$ 84,225	$ 192,690	$ 186,401

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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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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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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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount of tax expense (benefit), before reclassification adjustments, related to increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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