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Stock Incentive Plans - Summary of Share-based Awards Available for Grant under 2016 Plan (Details) - 2016 Plan - shares
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share-Based Awards Available for Grant      
Beginning balance (in shares) 5,528,132 4,717,292 4,034,152
Additional options authorized (in shares) 1,333,928 1,218,402 1,168,865
Awards granted (in shares) (595,915) (649,911) (666,913)
Awards forfeited (in shares) 156,623 181,513 124,478
Awards withheld for tax purposes (in shares) 82,622 60,836 56,710
Ending balance (in shares) 6,505,390 5,528,132 4,717,292