Accumulated Other Comprehensive Income (Loss) - Schedule of Reclassifications Out of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Nov. 30, 2018	Nov. 30, 2017	Nov. 30, 2018	Nov. 30, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	$ 24,880	$ 29,129	$ 49,184	$ 59,446
Income taxes	(77,530)	(68,636)	(106,403)	(126,607)
Net income	242,994	137,737	455,541	298,845
Reclassifications out of Accumulated Other Comprehensive Income (Loss) | Unrealized Income on Interest Rate Hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income taxes	(180)	(106)	(359)	(212)
Net income	294	172	589	344
Reclassifications out of Accumulated Other Comprehensive Income (Loss) | Unrealized Income on Interest Rate Hedges | Interest Rate Locks
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	$ 474	$ 278	$ 948	$ 556