v3.21.2
Stock-Based Compensation - Market Stock Unit Activity (Details) - Market Stock Units
shares in Thousands
9 Months Ended
Sep. 30, 2021
$ / shares
shares
Number of Shares  
Nonvested as of beginning of period (in shares) | shares 370
Granted (in shares) | shares 101
Change in awards based on performance (in shares) | shares 206
Vested (in shares) | shares (386)
Forfeited (in shares) | shares (21)
Nonvested as of end of period (in shares) | shares 270
Weighted Average Grant Date Fair Value  
Nonvested at beginning of period (in dollars per share) | $ / shares $ 35.67
Granted (in dollars per share) | $ / shares 80.11
Change in awards based on performance (in dollars per share) | $ / shares 39.67
Vested (in dollars per share) | $ / shares 33.62
Forfeited (in dollars per share) | $ / shares 44.67
Nonvested at end of period (in dollars per share) | $ / shares $ 57.58