Goodwill and Other Intangible Assets, net - Intangible Assets and their Related Useful Lives (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Intangible assets, net	$ 4,546	$ 9,448
Acquired technology [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	20,441	20,441
Intangible assets, accumulated amortization	(16,103)	(12,049)
Intangible assets, net	$ 4,338	8,392
Acquired technology [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, useful life	5 years
Acquired technology [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, useful life	7 years
Perpetual software licenses [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, useful life	2 years
Intangible assets, gross	$ 2,430	2,430
Intangible assets, accumulated amortization	(2,430)	(2,430)
Intangible assets, net	0	0
Covenant not to compete [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	2,028	2,028
Intangible assets, accumulated amortization	(1,976)	(1,634)
Intangible assets, net	$ 52	394
Covenant not to compete [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, useful life	1 year
Covenant not to compete [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, useful life	4 years
Other [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 1,939	1,939
Intangible assets, accumulated amortization	(1,783)	(1,277)
Intangible assets, net	$ 156	$ 662
Other [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, useful life	2 years
Other [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, useful life	7 years