v2.4.0.6
Fair Value Measurements (Narrative) (Detail) (USD $)
In Millions, unless otherwise specified
Sep. 30, 2012
Dec. 31, 2011
Sep. 30, 2011
Debt Instrument [Line Items]      
Debt instrument, carrying value $ 9.6 $ 14.5 $ 16.1
Secured Debt [Member]
     
Debt Instrument [Line Items]      
Debt instrument, carrying value $ 37.6 $ 38.2 $ 38.4