Share-Based Compensation Plans - Summary of Stock Option Activity (Detail) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of shares, issued	596,995
Exercisable at December 31, 2015	0
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of shares, outstanding, beginning balance	3,168,067
Number of shares, issued	599,745
Number of shares, exercised	(31,168)
Number of shares, forfeited	(2,200)
Number of shares, expired	(2,683)
Number of shares, outstanding, ending balance	3,731,761
Exercisable at December 31, 2015	707,745
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Weighted-average exercise price, outstanding (usd per share), beginning balance | $ / shares	$ 12.61
Weighted-average exercise price, issued (usd per share) | $ / shares	23.36
Weighted-average exercise price, exercised (usd per share) | $ / shares	10.53
Weighted-average exercise price, forfeited (usd per share) | $ / shares	17.65
Weighted-average exercise price, expired (usd per share) | $ / shares	29.33
Weighted-average exercise price, outstanding (usd per share), ending balance | $ / shares	14.33
Weighted-average exercise price, exercisable (usd per share) | $ / shares	$ 9.19
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted-average remaining contractual term in years, outstanding (years)	6 years 9 months 11 days
Weighted-average remaining contractual term in years, exercisable (years)	4 years 4 months 17 days
Aggregate intrinsic value, exercised | $	$ 455
Aggregate intrinsic value, outstanding | $	48,086
Aggregate intrinsic value, exercisable | $	$ 12,760