Stock-Based Compensation - Option Activity (Detail) - Stock Option [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Shares
Outstanding, Beginning Balance (in shares)	569	678
Options granted (in shares)	0	8
Options exercised (in shares)	(15)	(29)
Options canceled/forfeited (in shares)	(144)	(88)
Outstanding, Ending Balance (in shares)	410	569
Options exercisable (in shares)	143
Shares available for future grant (in shares)	2,063
Weighted Average Exercise Price
Outstanding, Beginning Balance (in dollars per share)	$ 14.74	$ 14.90
Options granted (in dollars per share)	0.00	11.33
Options exercised (in dollars per share)	12.29	10.16
Options canceled/forfeited (in dollars per share)	15.21	17.20
Outstanding, Ending Balance (in dollars per share)	14.66	$ 14.74
Options exercisable (in dollars per share)	$ 16.18
Weighted Average Remaining Contractual Life
Outstanding, contractual life (in years)	2 years 4 months 21 days
Options exercisable (in years)	1 year 7 months 17 days
Aggregate Intrinsic Value
Outstanding intrinsic value	$ 0
Options exercisable	$ 0