Income Taxes - Unrecognized Tax Benefits (Detail) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Income Tax Disclosure [Abstract]    
Beginning Balance $ 6.4 $ 6.4
Change in balances related to tax positions      
Ending Balance $ 6.4 $ 6.4