Consolidated Condensed Statements of Comprehensive Income (Unaudited) - 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
Statement of Comprehensive Income [Abstract]
Net income	$ 117,341			$ 94,883			$ 562,622	$ 325,403
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	(2,405)			(22,237)			(19,044)	(34,130)
Cumulative translation adjustment on investment in Shred-it Partnership	0			0			6,472	0
Change in fair value of derivatives	(14,070)			(29)			(14,070)	(33)
Amortization of interest rate lock agreements	488			488			1,464	1,464
Change in fair value of available-for-sale securities	(7)			5			(25)	8
Other comprehensive loss	(15,994)	$ 2,324	$ (11,533)	(21,773)	$ (9,308)	$ (1,610)	(25,203)	(32,691)
Comprehensive income	$ 101,347			$ 73,110			$ 537,419	$ 292,712