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Stock-Based Compensation - Summary of Restricted Stock Activity (Details) - Restricted Stock Units - $ / shares
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Number of Shares      
Non-vested balance at beginning of period (in shares) 1,620,568 1,290,450 1,461,910
Granted (in shares) 338,737 875,352 357,058
Vested (in shares) (379,936) (401,379) (385,454)
Canceled and forfeited (in shares) (180,242) (143,855) (143,064)
Non-vested balance at end of period (in shares) 1,399,127 1,620,568 1,290,450
Weighted Average Grant-Date Fair Value per Share      
Non-vested balance at beginning of period (in USD per share) $ 27.27 $ 20.52 $ 17.68
Granted (in USD per share) 32.11 34.32 28.06
Vested (in USD per share) 26.98 23.04 17.36
Canceled and forfeited (in USD per share) 25.66 21.46 18.89
Non-vested balance at end of period (in USD per share) $ 28.72 $ 27.27 $ 20.52