Preferred Share Purchase Rights - Additional Information (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Accelerated Share Repurchases [Line Items]
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, par value	$ 0.01	$ 0.01
Series A Junior Participating Preferred Stock [Member]
Accelerated Share Repurchases [Line Items]
Preferred stock, shares authorized	250,000