v2.4.0.6
Stock-Based Compensation (Details 1) (USD $)
In Millions, except Share data, unless otherwise specified
3 Months Ended
Mar. 31, 2013
Restricted stock unit and restricted stock activity  
Number of Restricted Stock Units and Shares of Restricted Stock, Other stock awards, beginning balance (in shares) 905,300
Number of Restricted Stock Units and Shares of Restricted Stock, Granted (in shares) 312,700
Number of Restricted Stock Units and Shares of Restricted Stock, Vested and issued (in shares) (59,700)
Number of Restricted Stock Units and Shares of Restricted Stock, Forfeited (in shares) 0
Number of Restricted Stock Units and Shares of Restricted Stock, Other stock awards, ending balance (in shares) 1,158,300
Number of Restricted Stock Units and Shares of Restricted Stock, Vested and unissued (in shares) 741,100
Weighted Average Grant Date Fair Value per Share, Other stock awards, beginning balance (in dollars per share) $ 27.51
Weighted Average Grant Date Fair Value per Share, Granted (in dollars per share) $ 30.33
Weighted Average Grant Date Fair Value per Share, Vested and Issued (in dollars per share) $ 27.14
Weighted Average Grant Date Fair Value per Share, Forfeited (in dollars per share) $ 0.00
Weighted Average Grant Date Fair Value per Share, Other stock awards, ending balance (in dollars per share) $ 28.30
Weighted Average Grant Date Fair Value per Share, Vested and Unissued (in dollars per share) $ 21.81
Weighted Average Remaining Contractual Term (years), Other stock awards 9 months 18 days
Aggregate Intrinsic Value, Other stock awards $ 38.2