Stock-Based Compensation - Summary of Changes in Number of Shares of Restricted Stock and Restricted Stock Units (Details) shares in Thousands	9 Months Ended
	Sep. 30, 2021 $ / shares shares
Shares
Shares outstanding, beginning of period (in shares) | shares	174
Granted (in shares) | shares	213
Vested (in shares) | shares	(72)
Canceled or forfeited (in shares) | shares	(29)
Shares outstanding, end of period (in shares) | shares	286
Weighted Average Grant Date Fair Value
Weighted average grant date fair value, beginning of period (in dollars per share) | $ / shares	$ 265.29
Weighted average grant date fair value, granted (in dollars per share) | $ / shares	272.83
Weighted average grant date fair value, vested (in dollars per share) | $ / shares	258.16
Weighted average grant date fair value, canceled or forfeited (in dollars per share) | $ / shares	283.14
Weighted average grant date fair value, end of period (in dollars per share) | $ / shares	$ 278.40