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Stock-Based Compensation - Schedule of Nonvested Share Activity (Details) - $ / shares
1 Months Ended 12 Months Ended
Apr. 30, 2015
Dec. 31, 2017
Restricted Stock    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]    
Unvested beginning balance (in shares)   39,028
Number of shares of other than options granted during the period (in shares) 80,548 0
Vested (in shares)   (11,058)
Forfeited (in shares)   (5,544)
Unvested ending balance (in shares)   22,426
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]    
Weighted average grant date fair value beginning (in dollars per share)   $ 86.92
Granted (in dollars per share)   0
Vested (in dollars per share)   86.92
Cancelled (in dollars per share)   86.92
Weighted average grant date fair value ending (in dollars per share)   $ 86.92
Performance Shares    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]    
Unvested beginning balance (in shares)   465,117
Number of shares of other than options granted during the period (in shares)   267,902
Vested (in shares)   (72,891)
Forfeited (in shares)   (66,029)
Unvested ending balance (in shares)   594,099
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]    
Weighted average grant date fair value beginning (in dollars per share)   $ 44.08
Granted (in dollars per share)   25.87
Vested (in dollars per share)   96.59
Cancelled (in dollars per share)   27.72
Weighted average grant date fair value ending (in dollars per share)   $ 29.18