Accumulated Other Comprehensive Income (Loss) - Schedule of Reclassifications Out of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Feb. 28, 2018	Feb. 28, 2017	Feb. 28, 2018	Feb. 28, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	$ 25,901	$ 13,696	$ 85,347	$ 41,135
Income taxes	121,282	(61,352)	(5,325)	(180,244)
Net income	295,789	116,954	594,634	375,112
Reclassifications out of Accumulated Other Comprehensive Income (Loss) | Unrealized Income on Cash Flow Hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income taxes	(180)	230	(392)	690
Net income	294	(385)	638	(1,155)
Reclassifications out of Accumulated Other Comprehensive Income (Loss) | Unrealized Income on Cash Flow Hedges | Interest Rate Locks
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	$ 474	$ (615)	$ 1,030	$ (1,845)