Accumulated Other Comprehensive Income (Loss) - Schedule of Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	May 31, 2018	May 31, 2017	May 31, 2016
AOCI, Net of Tax [Roll Forward]
Beginning Balance	$ 2,302,793	$ 1,842,659	$ 1,932,455
Other comprehensive income before reclassifications	20,305	20,769
Amounts reclassified from accumulated other comprehensive income (loss)	(933)	1,076
Other comprehensive income (loss), net of tax expense (benefit) of $690, $19,118 and ($9,813), respectively	19,372	21,845	(16,403)
Ending Balance	3,016,526	2,302,793	1,842,659
Foreign Currency
AOCI, Net of Tax [Roll Forward]
Beginning Balance	(12,726)	(2,474)
Other comprehensive income before reclassifications	19,276	(10,252)
Amounts reclassified from accumulated other comprehensive income (loss)	0	0
Other comprehensive income (loss), net of tax expense (benefit) of $690, $19,118 and ($9,813), respectively	19,276	(10,252)
Ending Balance	6,550	(12,726)	(2,474)
Unrealized (Loss) Gain on Cash Flow Hedges
AOCI, Net of Tax [Roll Forward]
Beginning Balance	11,382	(20,830)
Other comprehensive income before reclassifications	0	31,136
Amounts reclassified from accumulated other comprehensive income (loss)	(933)	1,076
Other comprehensive income (loss), net of tax expense (benefit) of $690, $19,118 and ($9,813), respectively	(933)	32,212
Ending Balance	10,449	11,382	(20,830)
Other
AOCI, Net of Tax [Roll Forward]
Beginning Balance	(1,685)	(1,570)
Other comprehensive income before reclassifications	1,029	(115)
Amounts reclassified from accumulated other comprehensive income (loss)	0	0
Other comprehensive income (loss), net of tax expense (benefit) of $690, $19,118 and ($9,813), respectively	1,029	(115)
Ending Balance	(656)	(1,685)	(1,570)
Other Accumulated Comprehensive Income (Loss)
AOCI, Net of Tax [Roll Forward]
Beginning Balance	(3,029)	(24,874)	(8,471)
Ending Balance	$ 16,343	$ (3,029)	$ (24,874)