Stock-Based Compensation - Summary of Changes in Number of Shares of Restricted Stock and Restricted Stock Units (Details)	9 Months Ended
	Sep. 30, 2020 $ / shares shares
Shares
Shares outstanding, beginning of period (in shares) | shares	243,000
Granted (in shares) | shares	171,000
Vested (in shares) | shares	(130,000)
Canceled or forfeited (in shares) | shares	(97,000)
Shares outstanding, end of period (in shares) | shares	187,000
Weighted Average Grant Date Fair Value
Weighted average grant date fair value, beginning of period (in dollars per share) | $ / shares	$ 246.34
Weighted average grant date fair value, granted (in dollars per share) | $ / shares	259.35
Weighted average grant date fair value, vested (in dollars per share) | $ / shares	223.48
Weighted average grant date fair value, canceled or forfeited (in dollars per share) | $ / shares	256.92
Weighted average grant date fair value, end of period (in dollars per share) | $ / shares	$ 261.94