Stockholders' Equity - Summary of Status of Stock Incentive Plans and Changes During Periods (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Number of Options
Beginning balance (in shares)	434,401	501,202	691,082
Options granted (in shares)	0	0	0
Awards exercised (in shares)	(55,382)	(46,198)	(171,897)
Options forfeited (in shares)	(49,147)	(20,603)	(17,983)
Ending balance (in shares)	329,872	434,401	501,202
Weighted Average Exercise Price
Beginning balance (in dollars per share)	$ 30.04	$ 28.82	$ 26.59
Options granted (in dollars per share)	0.00	0.00	0.00
Awards exercised (in dollars per share)	3.29	13.66	18.92
Options forfeited (in dollars per share)	35.97	37.04	37.64
Ending balance (in dollars per share)	$ 33.65	$ 30.04	$ 28.82
Weighted Average Contractual Life and Aggregate Intrinsic Value
Weighted average contractual life outstanding	1 year 3 months 18 days	2 years 1 month 21 days	3 years 18 days
Aggregate intrinsic value outstanding	$ 359	$ 3,080	$ 7,343
Number of options exercisable (in shares)	329,872	434,401	445,564
Weighted average exercise price exercisable (in dollars per share)	$ 33.65	$ 30.04	$ 27.73
Weighted average contractual life exercisable	1 year 3 months 18 days	2 years 1 month 21 days	2 years 11 months 5 days
Aggregate intrinsic value exercisable	$ 359	$ 3,080	$ 7,012