Subsequent Events (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		2 Months Ended	12 Months Ended
	Feb. 09, 2018	Jan. 31, 2018	Feb. 27, 2018	Dec. 31, 2017
Subsequent Event [Line Items]
Contractual commitment due within the next year				$ 12,000
Contractual commitment due within two years				6,500
Contractual commitment due within three years				$ 700
Common stock repurchased (in shares)				635,000
Average repurchase price (usd per share)				$ 35.55
Value of shares repurchased				$ 22,599
Restricted stock units
Subsequent Event [Line Items]
Awards granted (in shares)				1,938,000
Software Subscription Agreement
Subsequent Event [Line Items]
Contractual commitment due within the next year				$ 8,400
Contractual commitment due within two years				5,300
Contractual commitment due within three years				$ 500
2010 Plan | Restricted stock units
Subsequent Event [Line Items]
Awards granted (in shares)				1,937,900
Subsequent Event
Subsequent Event [Line Items]
Common stock repurchased (in shares)	300,000
Average repurchase price (usd per share)	$ 37.03
Value of shares repurchased	$ 9,900
Subsequent Event | Restricted stock units
Subsequent Event [Line Items]
Awards granted (in shares)			64,635
Award vesting period			4 years
Subsequent Event | Software Subscription Agreement
Subsequent Event [Line Items]
Contractual commitment due within the next year			$ 3,100
Contractual commitment due within two years			3,100
Contractual commitment due within three years			$ 3,100
Subsequent Event | Employee Stock Purchase Plan
Subsequent Event [Line Items]
Share increase under plan (in shares)		575,119
Subsequent Event | 2010 Plan
Subsequent Event [Line Items]
Share increase under plan (in shares)		2,588,036