Quarterly report pursuant to Section 13 or 15(d)

Equity-Based Compensation - Stock Options (Details)

v3.4.0.3
Equity-Based Compensation - Stock Options (Details) - Stock options - USD ($)
$ / shares in Units, $ in Millions
3 Months Ended 12 Months Ended
Mar. 31, 2016
Dec. 31, 2015
Stock options    
Outstanding at the beginning of the period (in shares) 720,887  
Options forfeited (in shares) (1,000)  
Outstanding at the end of the period (in shares) 719,887 720,887
Vested or expected to vest (in shares) 719,887  
Exercisable (in shares) 51,021  
Weighted average exercise price    
Outstanding at the beginning of the period (in dollars per share) $ 50.44  
Options forfeited (in dollars per share) 50.00  
Outstanding at the end of the period (in dollars per share) 50.44 $ 50.44
Vested or expected to vest (in dollars per share) 50.44  
Exercisable (in dollars per share) $ 53.79  
Weighted average remaining contractual life    
Outstanding 8 years 10 months 21 days 9 years 1 month 21 days
Vested or expected to vest 8 years 10 months 21 days  
Exercisable 7 years 9 months  
Weighted-average assumptions used to calculate fair value of stock options granted    
Volatility (as a percent)   40.00%
Risk-free interest rate (as a percent)   1.66%
Expected life   6 years 3 months
Weighted average fair value of options granted (in dollars per share)   $ 14.74
Additional disclosures    
Unrecognized stock-based compensation expense $ 7.6  
Weighted average period for recognizing unrecognized stock-based compensation expense 2 years 10 months 24 days  
Minimum    
Stock-based compensation    
Vesting period 1 year  
Maximum    
Stock-based compensation    
Vesting period 4 years  
Contractual life 10 years