XML 68 R44.htm IDEA: XBRL DOCUMENT v2.4.0.8
Share-Based Compensation - Summary of Activity of the Outstanding Share-Based Compensation Awards (Detail) (USD $)
9 Months Ended
Sep. 30, 2013
Sep. 30, 2012
Restricted Stock [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Beginning Balance, Shares 516,351  
Granted, Shares 101,300  
Vested, Shares (161,186)  
Forfeited, Shares (5,966)  
Ending Balance, Shares 450,499  
Beginning Balance, Weighted-Average Grant Date Fair Value $ 21.25  
Granted, Weighted-Average Grant Date Fair Value $ 27.28  
Vested, Weighted-Average Grant Date Fair Value $ 20.74  
Forfeited, Weighted-Average Grant Date Fair Value $ 23.07  
Ending Balance, Weighted-Average Grant Date Fair Value $ 22.76  
Restricted Stock Units [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Beginning Balance, Shares 40,500  
Granted, Shares 8,600  
Vested, Shares (11,300)  
Forfeited, Shares (8,840)  
Ending Balance, Shares 28,960  
Beginning Balance, Weighted-Average Grant Date Fair Value $ 20.82  
Granted, Weighted-Average Grant Date Fair Value $ 27.35  
Vested, Weighted-Average Grant Date Fair Value $ 19.10  
Forfeited, Weighted-Average Grant Date Fair Value $ 22.33  
Ending Balance, Weighted-Average Grant Date Fair Value $ 22.98  
Performance Unit Incentive Plan (PUP) [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Beginning Balance, Shares 210,600  
Granted, Shares 93,100  
Vested, Shares 0 0
Forfeited, Shares (432)  
Ending Balance, Shares 303,268  
Beginning Balance, Weighted-Average Grant Date Fair Value $ 21.70  
Granted, Weighted-Average Grant Date Fair Value $ 27.35  
Forfeited, Weighted-Average Grant Date Fair Value $ 20.60  
Ending Balance, Weighted-Average Grant Date Fair Value $ 23.43