Accumulated Other Comprehensive Income (Loss) - Schedule of Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	May 31, 2017	May 31, 2016	May 31, 2015
AOCI, Net of Tax [Roll Forward]
Beginning Balance	$ 1,842,659	$ 1,932,455	$ 2,192,858
Other comprehensive income (loss), net of tax expense (benefit) of $19,118, ($9,813), and $1,043, respectively	21,845	(16,403)	(36,899)
Ending Balance	2,302,793	1,842,659	1,932,455
Foreign Currency
AOCI, Net of Tax [Roll Forward]
Beginning Balance	(2,474)	2,987
Other comprehensive (loss) income before reclassifications	(10,252)	(11,933)
Amounts reclassified from accumulated other comprehensive income (loss)	0	6,472
Other comprehensive income (loss), net of tax expense (benefit) of $19,118, ($9,813), and $1,043, respectively	(10,252)	(5,461)
Ending Balance	(12,726)	(2,474)	2,987
Unrealized (Loss) Gain on Cash Flow Hedges
AOCI, Net of Tax [Roll Forward]
Beginning Balance	(20,830)	(10,626)
Other comprehensive (loss) income before reclassifications	31,136	(12,156)
Amounts reclassified from accumulated other comprehensive income (loss)	1,076	1,952
Other comprehensive income (loss), net of tax expense (benefit) of $19,118, ($9,813), and $1,043, respectively	32,212	(10,204)
Ending Balance	11,382	(20,830)	(10,626)
Other
AOCI, Net of Tax [Roll Forward]
Beginning Balance	(1,570)	(832)
Other comprehensive (loss) income before reclassifications	(115)	(738)
Amounts reclassified from accumulated other comprehensive income (loss)	0	0
Other comprehensive income (loss), net of tax expense (benefit) of $19,118, ($9,813), and $1,043, respectively	(115)	(738)
Ending Balance	(1,685)	(1,570)	(832)
Other Accumulated Comprehensive Income (Loss)
AOCI, Net of Tax [Roll Forward]
Beginning Balance	(24,874)	(8,471)	28,428
Other comprehensive (loss) income before reclassifications	20,769	(24,827)
Amounts reclassified from accumulated other comprehensive income (loss)	1,076	8,424
Other comprehensive income (loss), net of tax expense (benefit) of $19,118, ($9,813), and $1,043, respectively	21,845	(16,403)
Ending Balance	$ (3,029)	$ (24,874)	$ (8,471)