Accumulated Other Comprehensive Income (Loss) - Schedule of Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Feb. 29, 2016	Nov. 30, 2015	Aug. 31, 2015	Feb. 28, 2015	Nov. 30, 2014	Aug. 31, 2014	Feb. 29, 2016	Feb. 28, 2015
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning Balance	$ (17,680)	$ (20,004)	$ (8,471)	$ 17,510	$ 26,818	$ 28,428	$ (8,471)	$ 28,428
Other comprehensive loss before reclassifications	(16,482)	(4,636)	(12,021)	(22,261)	(9,796)	(2,098)
Amounts reclassified from accumulated other comprehensive income (loss)	488	6,960	488	488	488	488
Other comprehensive loss	(15,994)	2,324	(11,533)	(21,773)	(9,308)	(1,610)	(25,203)	(32,691)
Ending Balance	(33,674)	(17,680)	(20,004)	(4,263)	17,510	26,818	(33,674)	(4,263)
Foreign Currency
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning Balance	(7,180)	(9,026)	2,987	29,632	39,410	41,525	2,987	41,525
Other comprehensive loss before reclassifications	(2,405)	(4,626)	(12,013)	(22,237)	(9,778)	(2,115)
Amounts reclassified from accumulated other comprehensive income (loss)	0	6,472	0	0	0	0
Other comprehensive loss	(2,405)	1,846	(12,013)	(22,237)	(9,778)	(2,115)
Ending Balance	(9,585)	(7,180)	(9,026)	7,395	29,632	39,410	(9,585)	7,395
Unrealized Loss on Derivatives
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning Balance	(9,650)	(10,138)	(10,626)	(11,643)	(12,110)	(12,615)	(10,626)	(12,615)
Other comprehensive loss before reclassifications	(14,070)	0	0	(29)	(21)	17
Amounts reclassified from accumulated other comprehensive income (loss)	488	488	488	488	488	488
Other comprehensive loss	(13,582)	488	488	459	467	505
Ending Balance	(23,232)	(9,650)	(10,138)	(11,184)	(11,643)	(12,110)	(23,232)	(11,184)
Other
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning Balance	(850)	(840)	(832)	(479)	(482)	(482)	(832)	(482)
Other comprehensive loss before reclassifications	(7)	(10)	(8)	5	3	0
Amounts reclassified from accumulated other comprehensive income (loss)	0	0	0	0	0	0
Other comprehensive loss	(7)	(10)	(8)	5	3	0
Ending Balance	$ (857)	$ (850)	$ (840)	$ (474)	$ (479)	$ (482)	$ (857)	$ (474)