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Stock-Based Compensation - Summary of RSU Activity (Details) - Restricted Stock Units (RSUs) - $ / shares
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Units      
Nonvested at beginning of period (in shares) 21,206    
Grants in period (in shares) 289,575    
Vested (in shares) (8,820)    
Forfeited or expired (in shares) (4,063)    
Nonvested at end of period (in shares) 297,898 21,206  
Weighted Average Grant Date Fair Value      
Nonvested at beginning of period (in USD per share) $ 56.30    
Granted (in USD per share) 32.36 $ 56.13 $ 78.22
Vested (in USD per share) 55.51    
Forfeited or expired (in USD per share) 38.99    
Nonvested at end of period (in USD per share) $ 32.63 $ 56.30