XML 65 R60.htm IDEA: XBRL DOCUMENT v2.4.0.6
Share-Based Payment Arrangements - Additional Information (Detail) (USD $)
In Millions, except Share data, unless otherwise specified
9 Months Ended 9 Months Ended
Sep. 30, 2012
Sep. 30, 2011
May 24, 2012
Sep. 30, 2012
Performance Share Awards [Member]
May 24, 2012
Performance Share Awards [Member]
Jan. 26, 2012
Performance Share Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Stock option ,granted     152,140      
Fair Value on grant date     $ 8.43      
Fair value method used Black-Scholes-Merton option-pricing model          
Intrinsic value of options exercised $ 0.5 $ 0.1        
Shares granted to key members of executives and senior management         12,939 14,858
Fair value of shares granted         $ 36.16  
Percentage of maximum number of shares earned of target award       200.00%    
Shareholder return period 3 years          
Unrecognized compensation cost 30.4          
Weighted-average period in years 3 years 3 months 18 days          
Total fair value of shares vested $ 0.9 $ 8.0