Stock-Based Compensation (Details 3) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 9 Months Ended |
Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2015 | Sep. 30, 2014 |
Stock options | | | | |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range | | | | |
Total intrinsic value of stock options exercised during the period | $ 0.7 | $ 0.8 | $ 4.6 | $ 1.5 |
Unrecognized compensation expense related to unvested stock options | 30.5 | | $ 30.5 | |
Expected weighted average period for recognizing unrecognized compensation expense | | | 2 years 7 months 6 days | |
Performance shares | | | | |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range | | | | |
Unrecognized compensation expense related to unvested stock options | $ 1.4 | | $ 1.4 | |
$3.03 to $3.29 | | | | |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range | | | | |
Range of Exercise Prices lower range limit (in dollars per share) | | | $ 3.03 | |
Range of Exercise Prices upper range limit (in dollars per share) | | | $ 3.29 | |
Number of Options outstanding (in shares) | 153,878 | | 153,878 | |
Weighted Average Remaining Contractual Term | | | 6 years 3 months 4 days | |
Outstanding Options, Weighted Average Exercise Price (in dollars per share) | $ 3.05 | | $ 3.05 | |
Number of Options exercisable (in shares) | 128,915 | | 128,915 | |
Exercisable Options, Weighted Average Exercise Price (in dollars per share) | $ 3.05 | | $ 3.05 | |
$3.40 to $3.40 | | | | |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range | | | | |
Range of Exercise Prices lower range limit (in dollars per share) | | | 3.40 | |
Range of Exercise Prices upper range limit (in dollars per share) | | | $ 3.40 | |
Number of Options outstanding (in shares) | 708,314 | | 708,314 | |
Weighted Average Remaining Contractual Term | | | 6 years 11 months 12 days | |
Outstanding Options, Weighted Average Exercise Price (in dollars per share) | $ 3.40 | | $ 3.40 | |
Number of Options exercisable (in shares) | 531,236 | | 531,236 | |
Exercisable Options, Weighted Average Exercise Price (in dollars per share) | $ 3.40 | | $ 3.40 | |
$3.60 to $6.90 | | | | |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range | | | | |
Range of Exercise Prices lower range limit (in dollars per share) | | | 3.60 | |
Range of Exercise Prices upper range limit (in dollars per share) | | | $ 6.90 | |
Number of Options outstanding (in shares) | 584,572 | | 584,572 | |
Weighted Average Remaining Contractual Term | | | 7 years 2 months 12 days | |
Outstanding Options, Weighted Average Exercise Price (in dollars per share) | $ 6.01 | | $ 6.01 | |
Number of Options exercisable (in shares) | 343,412 | | 343,412 | |
Exercisable Options, Weighted Average Exercise Price (in dollars per share) | $ 5.95 | | $ 5.95 | |
$6.96 to $12.44 | | | | |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range | | | | |
Range of Exercise Prices lower range limit (in dollars per share) | | | 6.96 | |
Range of Exercise Prices upper range limit (in dollars per share) | | | $ 12.44 | |
Number of Options outstanding (in shares) | 702,620 | | 702,620 | |
Weighted Average Remaining Contractual Term | | | 7 years 7 months 28 days | |
Outstanding Options, Weighted Average Exercise Price (in dollars per share) | $ 11.34 | | $ 11.34 | |
Number of Options exercisable (in shares) | 351,382 | | 351,382 | |
Exercisable Options, Weighted Average Exercise Price (in dollars per share) | $ 11.23 | | $ 11.23 | |
$12.58 to $13.94 | | | | |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range | | | | |
Range of Exercise Prices lower range limit (in dollars per share) | | | 12.58 | |
Range of Exercise Prices upper range limit (in dollars per share) | | | $ 13.94 | |
Number of Options outstanding (in shares) | 545,475 | | 545,475 | |
Weighted Average Remaining Contractual Term | | | 8 years 7 months 28 days | |
Outstanding Options, Weighted Average Exercise Price (in dollars per share) | $ 12.77 | | $ 12.77 | |
Number of Options exercisable (in shares) | 131,828 | | 131,828 | |
Exercisable Options, Weighted Average Exercise Price (in dollars per share) | $ 12.78 | | $ 12.78 | |
$14.04 to $16.07 | | | | |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range | | | | |
Range of Exercise Prices lower range limit (in dollars per share) | | | 14.04 | |
Range of Exercise Prices upper range limit (in dollars per share) | | | $ 16.07 | |
Number of Options outstanding (in shares) | 808,650 | | 808,650 | |
Weighted Average Remaining Contractual Term | | | 8 years 9 months | |
Outstanding Options, Weighted Average Exercise Price (in dollars per share) | $ 15.34 | | $ 15.34 | |
Number of Options exercisable (in shares) | 120,324 | | 120,324 | |
Exercisable Options, Weighted Average Exercise Price (in dollars per share) | $ 14.43 | | $ 14.43 | |
$16.19 to $20.49 | | | | |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range | | | | |
Range of Exercise Prices lower range limit (in dollars per share) | | | 16.19 | |
Range of Exercise Prices upper range limit (in dollars per share) | | | $ 20.49 | |
Number of Options outstanding (in shares) | 646,581 | | 646,581 | |
Weighted Average Remaining Contractual Term | | | 8 years 7 months 2 days | |
Outstanding Options, Weighted Average Exercise Price (in dollars per share) | $ 19.53 | | $ 19.53 | |
Number of Options exercisable (in shares) | 174,573 | | 174,573 | |
Exercisable Options, Weighted Average Exercise Price (in dollars per share) | $ 19.65 | | $ 19.65 | |
$20.92 to $22.14 | | | | |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range | | | | |
Range of Exercise Prices lower range limit (in dollars per share) | | | 20.92 | |
Range of Exercise Prices upper range limit (in dollars per share) | | | $ 22.14 | |
Number of Options outstanding (in shares) | 107,300 | | 107,300 | |
Weighted Average Remaining Contractual Term | | | 9 years 4 months 24 days | |
Outstanding Options, Weighted Average Exercise Price (in dollars per share) | $ 21.54 | | $ 21.54 | |
Number of Options exercisable (in shares) | 5,625 | | 5,625 | |
Exercisable Options, Weighted Average Exercise Price (in dollars per share) | $ 21.54 | | $ 21.54 | |
$22.76 to $22.76 | | | | |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range | | | | |
Range of Exercise Prices lower range limit (in dollars per share) | | | 22.76 | |
Range of Exercise Prices upper range limit (in dollars per share) | | | $ 22.76 | |
Number of Options outstanding (in shares) | 823,700 | | 823,700 | |
Weighted Average Remaining Contractual Term | | | 9 years 7 months 24 days | |
Outstanding Options, Weighted Average Exercise Price (in dollars per share) | $ 22.76 | | $ 22.76 | |
$22.84 to $27.38 | | | | |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range | | | | |
Range of Exercise Prices lower range limit (in dollars per share) | | | 22.84 | |
Range of Exercise Prices upper range limit (in dollars per share) | | | $ 27.38 | |
Number of Options outstanding (in shares) | 159,500 | | 159,500 | |
Weighted Average Remaining Contractual Term | | | 9 years 8 months 5 days | |
Outstanding Options, Weighted Average Exercise Price (in dollars per share) | $ 23.80 | | $ 23.80 | |