Stock Plans and Other Incentives - Changes in RSUs (Parenthetical) (Detail) (USD $)				3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Mar. 31, 2013 RSU [Member] Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common stock used to settle minimum employee withholding tax obligations				70,897
Number of employees withholding tax obligations				16
Employee withholding tax obligations approximate amount				$ 1,109,000
Common stock delivered, net				109,177
Closing stock price	$ 18.05	$ 19.23	$ 15.54