Accumulated Other Comprehensive Income (Loss) - Schedule of Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Nov. 30, 2018	Aug. 31, 2018	Nov. 30, 2017	Aug. 31, 2017	Nov. 30, 2018	Nov. 30, 2017
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance		$ 3,016,526			$ 3,016,526
Other comprehensive income (loss) before reclassifications	$ (5,702)	(6,187)	$ (11,394)	$ 35,204
Amounts reclassified from accumulated other comprehensive income (loss)	(294)	(295)	(172)	(172)
Other comprehensive (loss) income	(5,996)	(6,482)	(11,566)	35,032	(12,478)	$ 23,466
Ending balance	3,027,244				3,027,244
Foreign Currency
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	3,531	6,550	22,458	(12,726)	6,550	(12,726)
Other comprehensive income (loss) before reclassifications	(10,623)	(3,019)	(11,374)	35,184
Amounts reclassified from accumulated other comprehensive income (loss)	0	0	0	0
Other comprehensive (loss) income	(10,623)	(3,019)	(11,374)	35,184
Ending balance	(7,092)	3,531	11,084	22,458	(7,092)	11,084
Unrealized Income on Interest Rate Hedges
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	6,986	10,449	11,210	11,382	10,449	11,382
Other comprehensive income (loss) before reclassifications	4,921	(3,168)	0	0
Amounts reclassified from accumulated other comprehensive income (loss)	(294)	(295)	(172)	(172)
Other comprehensive (loss) income	4,627	(3,463)	(172)	(172)
Ending balance	11,613	6,986	11,038	11,210	11,613	11,038
Other
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(656)	(656)	(1,665)	(1,685)	(656)	(1,685)
Other comprehensive income (loss) before reclassifications	0	0	(20)	20
Amounts reclassified from accumulated other comprehensive income (loss)	0	0	0	0
Other comprehensive (loss) income	0	0	(20)	20
Ending balance	(656)	(656)	(1,685)	(1,665)	(656)	(1,685)
Total
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	9,861	16,343	32,003	(3,029)	16,343	(3,029)
Ending balance	$ 3,865	$ 9,861	$ 20,437	$ 32,003	$ 3,865	$ 20,437

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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