Consolidated Condensed Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Feb. 28, 2019	Nov. 30, 2018	Aug. 31, 2018	Feb. 28, 2018	Nov. 30, 2017	Aug. 31, 2017	Feb. 28, 2019	Feb. 28, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 203,334	$ 243,013	$ 212,515	$ 302,095	$ 137,109	$ 217,211	$ 658,862	$ 656,415
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	5,025			2,374			(8,617)	26,184
Change in fair value of interest rate lock agreements	(8,183)			0			(6,430)	0
Amortization of interest rate lock agreements	(295)			(294)			(884)	(638)
Other comprehensive (loss) income	(3,453)	$ (5,996)	$ (6,482)	2,080	$ (11,566)	$ 35,032	(15,931)	25,546
Comprehensive income	$ 199,881			$ 304,175			$ 642,931	$ 681,961

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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