Final Fair Value of Consideration Transferred for Acquisition (Parenthetical) (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Common stock, par value	$ 0.01	$ 0.01
dbMotion [Member]
Business Acquisition [Line Items]
Common stock, shares	3,823,453
Common stock, par value	$ 0.01
Common stock, fair value	$ 12.57
dbMotion [Member] | Deferred Cash Consideration [Member]
Business Acquisition [Line Items]
Period of acquisition liability incurred	18 months
dbMotion [Member] | Subordinated Promissory Note [Member]
Business Acquisition [Line Items]
Period of acquisition liability incurred	18 months