v2.4.0.8
Commitments and Contingencies - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
6 Months Ended
Jun. 30, 2013
Commitment And Contingencies [Line Items]  
Annual interest expense $ 17.5
Senior Notes [Member]
 
Commitment And Contingencies [Line Items]  
Debt instrument payment of interest Semi-annually on June 15 and December 15, beginning December 15, 2013