Stock Incentive Plans - Summary of Information Concerning Stock Option Awards (Detail) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Weighted Average Price per Share, Options outstanding at beginning of year	$ 11.50	$ 13.21
Weighted Average Price per Share, Assumed from acquisition	$ 5.77
Weighted Average Price per Share, Exercised	$ 6.05
Weighted Average Price per Share, Forfeited	$ 25.79	$ 14.92
Weighted Average Price per Share, Options outstanding and exercisable at end of year	$ 8.71	$ 12.01
Shares, Options outstanding at beginning of year	533,524	640,050
Shares, Assumed from acquisition	304,785
Shares, Exercised	(87,332)
Shares, Forfeited	(48,172)	(263,589)
Shares, Options outstanding and exercisable at end of year	702,805	376,461