Goodwill and Intangibles - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	May. 31, 2015	May. 31, 2014	May. 31, 2013
Goodwill And Other Intangible Assets [Line Items]
Amortization of Intangible Assets	$ 129	$ 164	$ 164
EMT
Goodwill And Other Intangible Assets [Line Items]
Date of Acquisition	Aug. 24, 2011
Telogy LLC
Goodwill And Other Intangible Assets [Line Items]
Date of Acquisition	Mar. 31, 2010
Rush Computer Rentals, Inc.
Goodwill And Other Intangible Assets [Line Items]
Date of Acquisition	Jan. 31, 2006