Acquisitions - Additional Information (Detail) $ in Thousands	1 Months Ended			6 Months Ended
	Jul. 31, 2015 USD ($) Employee	Jun. 30, 2015 USD ($)	Aug. 31, 2014 USD ($)	Nov. 30, 2015 USD ($) shares	Nov. 30, 2014 USD ($)	Jul. 07, 2015 USD ($)	May. 31, 2015 USD ($)
Business Acquisition [Line Items]
Business acquisition, goodwill				$ 253,677			$ 107,773
Business acquisition total consideration, net of cash acquired				262,191	$ 2,949
Minimum [Member]
Business Acquisition [Line Items]
Acquired intangible asset useful life	1 year
Maximum [Member]
Business Acquisition [Line Items]
Acquired intangible asset useful life	15 years
Qualspec Group [Member]
Business Acquisition [Line Items]
Contingent consideration	$ 5,800			0
Business acquisition, purchase price	255,600
Business acquisition, contingent consideration	10,000
Increase in revenue due to acquisition	$ 180,000
Number of employees added | Employee	1,000
Business acquisition, fixed assets						$ 15,472
Business acquisition, goodwill						$ 145,440
Mechanical Service [Member]
Business Acquisition [Line Items]
Business acquisition, purchase price		$ 12,300
Business acquisition, contingent consideration		1,800
Business acquisitions, cash acquired		100
Business acquisition, net working capital		3,000
Business acquisition, fixed assets		600
Business acquisition, goodwill and intangible assets		8,800
Business acquisition, goodwill		$ 2,500
Business acquisition, contingent consideration thresholds period		3 years
Business acquisition, contingent consideration based upon achievement of performance targets		$ 4,000
Mechanical Service [Member] | United Kingdom [Member]
Business Acquisition [Line Items]
Business acquisition, contingent consideration			$ 300
Business acquisitions, cash acquired			200
Business acquisition, goodwill and intangible assets			1,000
Business acquisition total consideration, net of cash acquired			3,100
Business acquisition, allocated to fixed assets and net working capital			$ 2,100
Furmanite Corporation [Member] | Scenario, Plan [Member]
Business Acquisition [Line Items]
Acquired outstanding shares of stock value				$ 335,000
Shares received per each share of common stock | shares				0.215