Schedule of Amortizable Intangible Asset (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Goodwill and Other Intangible Assets [Line Items]
Cost	$ 127,435	$ 127,394
Accumulated Amortization	(89,591)	(83,203)
Net Book Value	37,844	44,191
Customer related intangibles
Goodwill and Other Intangible Assets [Line Items]
Cost	63,132	63,091
Accumulated Amortization	(41,322)	(37,573)
Net Book Value	21,810	25,518
Technology
Goodwill and Other Intangible Assets [Line Items]
Cost	58,942	58,942
Accumulated Amortization	(42,908)	(40,269)
Net Book Value	16,034	18,673
Other intangibles
Goodwill and Other Intangible Assets [Line Items]
Cost	5,361	5,361
Accumulated Amortization	$ (5,361)	$ (5,361)
Minimum | Customer related intangibles
Goodwill and Other Intangible Assets [Line Items]
Range of Useful Lives	4 years	4 years
Minimum | Technology
Goodwill and Other Intangible Assets [Line Items]
Range of Useful Lives	3 years	3 years
Maximum | Customer related intangibles
Goodwill and Other Intangible Assets [Line Items]
Range of Useful Lives	10 years	10 years
Maximum | Technology
Goodwill and Other Intangible Assets [Line Items]
Range of Useful Lives	10 years	10 years