Discontinued Operations - Schedule of Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Feb. 29, 2016	Feb. 28, 2015	Feb. 29, 2016	Feb. 28, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income tax benefit (expense)	$ 741	$ 3,494	$ (142,235)	$ (10,828)
Gain on Storage Transactions			15,786	35,036
Loss on investment in Shred-it Partnership			(24,288)	(4,570)
Gain on sale of investment in Shred-it Partnership			374,026	0
Net income (loss) from discontinued operations	62	(5,448)	223,692	15,466
Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue	0	0	0	31,379
(Loss) income before income taxes	(679)	940	403	(4,172)
Income tax benefit (expense)	264	(159)	(157)	2,063
Gain on Storage Transactions	0	899	15,786	35,036
Loss on investment in Shred-it Partnership	0	(10,781)	(24,288)	(4,570)
Gain on sale of investment in Shred-it Partnership	0	0	374,026	0
Income tax benefit (expense) on net gain (loss)	477	3,653	(142,078)	(12,891)
Net income (loss) from discontinued operations	$ 62	$ (5,448)	$ 223,692	$ 15,466