Annual report pursuant to Section 13 and 15(d)

Commitments and Contingencies - Additional Information (Detail)

v2.4.0.8
Commitments and Contingencies - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Commitments And Contingencies Disclosure [Abstract]      
Rental expense $ 15.7 $ 14.5 $ 15.1