v2.4.0.6
Commitments and Contingencies (Narrative) (Detail) (USD $)
In Millions, unless otherwise specified
3 Months Ended 9 Months Ended
Sep. 30, 2012
Sep. 30, 2011
Sep. 30, 2012
Sep. 30, 2011
Commitments and Contingencies Disclosure [Abstract]        
Total rent expense, under non-cancellable operating leases $ 2.3 $ 1.7 $ 6.2 $ 5.0