Intangible Assets - Summary of Intangible Assets (Detail) - USD ($) $ in Thousands	Nov. 30, 2015	May. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 116,902	$ 36,225
Accumulated Amortization	(20,384)	(15,957)
Net Carrying Amount	96,518	20,268
Customer relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	99,789	22,612
Accumulated Amortization	(12,412)	(9,111)
Net Carrying Amount	87,377	13,501
Non-compete agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	5,018	3,417
Accumulated Amortization	(3,460)	(3,363)
Net Carrying Amount	1,558	54
Trade names [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	6,300	4,401
Accumulated Amortization	(1,805)	(1,074)
Net Carrying Amount	4,495	3,327
Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	5,112	5,112
Accumulated Amortization	(2,496)	(2,230)
Net Carrying Amount	2,616	2,882
Licenses [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	683	683
Accumulated Amortization	(211)	(179)
Net Carrying Amount	$ 472	$ 504