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Share-Based Compensation - Information on Option Grants (Details) - Stock Options - $ / shares
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Number of options granted 544,209 312,141 669,658
Weighted average exercise price per share $ 33.32 $ 46.48 $ 28.30
Weighted average grant date fair value per share $ 12.29 $ 14.78 $ 8.66