v2.4.0.6
Stockholders' Equity and Stock Incentive Plans (Restricted Stock Units, Performance Stock Units and Career Shares) (Details) (USD $)
12 Months Ended 1 Months Ended 12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2012
Restricted Stock Units (RSUs)
Dec. 31, 2011
Restricted Stock Units (RSUs)
Dec. 31, 2010
Restricted Stock Units (RSUs)
Dec. 31, 2012
Performance Stock Units (PSUs)
Dec. 31, 2011
Performance Stock Units (PSUs)
Dec. 31, 2010
Performance Stock Units (PSUs)
Dec. 31, 2012
Career Shares
Dec. 31, 2011
Career Shares
Dec. 31, 2010
Career Shares
May 31, 2012
Director
Restricted Stock Units (RSUs)
Dec. 31, 2011
Director
Restricted Stock Units (RSUs)
Dec. 31, 2010
Director
Restricted Stock Units (RSUs)
Dec. 31, 2012
Executive Officer
Career Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                                
Share-based compensation expense $ 12,247,000 $ 9,996,000 $ 11,324,000 $ 5,816,000 $ 3,062,000 $ 1,759,000 $ 729,000 $ 76,000 $ 0 $ 1,068,000 $ 2,008,000 $ 461,000        
Non-Option Award Activity [Roll Forward]                                
Outstanding, beginning of period       1,849,390 1,436,095 970,108 406,602 0   539,689 432,862 304,441        
Granted       860,376 765,516 485,067 423,955 406,602   163,137 113,495 146,622 751,000 695,000 429,000  
Canceled       (9,781) (41,340) (19,080) (1,427) 0   0 (6,668) (18,201)        
Vested / awarded       (328,838) (310,881) 0 0 0   0 0 0        
Outstanding, end of period       2,371,147 1,849,390 1,436,095 829,130 406,602 0 702,826 539,689 432,862        
Outstanding, vested       955,693 573,798   0 0   441,736 314,888          
Granted, weighted average grant date fair value (in USD per share)       $ 5.51 $ 6.96 $ 8.36 $ 5.24 $ 6.70   $ 7.69 $ 10.81 $ 8.60        
Total unrecognized share-based compensation costs related to unvested stock options       $ 0     $ 6,800,000                  
Total unrecognized share-based compensation costs related to unvested stock options, period for recognition       2 years     2 years 6 months                  
Evaluation of performance conditions, period             3 years                  
Awards if no conditions met, percentage             0.00%                  
Awards if only threshhold performance met, percentage             50.00%                  
Awards for target performance, percentage             100.00%                  
Awards for maximum performance, percentage (up to 200%)             200.00%                  
Award vesting period             3 years                  
Award eligibility, minimum age                               55 years
Award requisite service period                               10 years
Service period, Tranche 1                               10 years
Service period, Tranche 2                               15 years
Service period, Tranche 3                               20 years