Share-based Compensation Plans and Awards - Restricted Stock Units (Details) (USD $)
In Thousands, except Per Share data, unless otherwise specified
9 Months Ended 3 Months Ended
Sep. 30, 2012
Restricted stock units (RSUs) [Member]
Sep. 30, 2012
Performance shares [Member]
Consultant [Member]
Sep. 30, 2012
Performance shares [Member]
Consultant [Member]
Common stock [Member]
RSUs and other restricted shares      
Unvested at period start 3,606    
Granted 2,789    
Vested (1,257)    
Forfeited (699)    
Unvested at period end 4,439    
Weighted average grant date fair value      
Unvested at period start, weighted average grant date fair value (usd per share) $ 12.19    
Granted, weighted average grant date fair value (usd per share) $ 7.55    
Vested, weighted average grant date fair value (usd per share) $ 10.83    
Forfeited,weighted average grant date fair value (usd per share) $ 10.99    
Unvested at period end, weighted average grant date fair value (usd per share) $ 9.75    
Unrecognized compensation cost related to non-vested RSUs and restricted shares $ 36 $ 423  
Unrecognized compensation cost, weighted average period of recognition 2 years 7 months 6 days    
Number of shares issued during period     50