Discontinued Operations - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Aug. 31, 2016	Aug. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of Storage assets	$ 0	$ 24,395
Gain on disposal of business	0	4,843
Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on disposal of business	$ 0	4,843
Discontinued Operations | Storage Real Estate Assets
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on investment in Shred-it, net of tax		9,300
Proceeds from sale of Storage assets		24,400
Gain on disposal of business		$ 4,800