Acquisitions - Additional Information (Detail) - LinkEx, Inc [Member] - USD ($)		3 Months Ended	12 Months Ended
	Feb. 02, 2015	Dec. 31, 2015	Dec. 31, 2015
Business Acquisition [Line Items]
Percentage of voting interest acquired	100.00%
Purchase price of acquisition	$ 22,200,000	$ 22,238,000
Potential earn-out subject to meeting profit targets	$ 3,000,000
Acquired intangible assets, amortization period			15 years
Identified intangible assets, weighted-average useful life			14 years 4 months 24 days