Share-Based Compensation - Share-Based Payment Award Activity (Details)	3 Months Ended	6 Months Ended
	Jun. 30, 2020 USD ($) $ / shares shares	Jun. 30, 2020 USD ($) $ / shares shares
Options
Outstanding, beginning of period, in shares | shares		625,407
Granted, in shares | shares		119,472
Exercised, in shares | shares		(82,896)
Forfeited, in shares | shares		(11,585)
Expired, in shares | shares	(1,030)
Outstanding, end of period, in shares | shares	649,368	649,368
Vested and expected to vest, end of period, in shares | shares	622,501	622,501
Exercisable, end of period, in shares | shares	367,008	367,008
Weighted Average Exercise Price
Outstanding, beginning of period, in usd per share | $ / shares		$ 169.33
Granted, in usd per share | $ / shares		185.52
Exercised, in usd per share | $ / shares		89.71
Forfeited, in usd per share | $ / shares		226.95
Expired, in usd per share | $ / shares	$ 71.11
Outstanding, end of period, in usd per share | $ / shares	181.60	181.60
Vested and expected to vest, end of period, in usd per share | $ / shares	180.01	180.01
Exercisable, end of period, in usd per share | $ / shares	$ 148.46	$ 148.46
Weighted Average Remaining Contractual Life - in Years
Outstanding, end of period		4 years 1 month 9 days
Vested and expected to vest, end of period		4 years 7 days
Exercisable, end of period		2 years 8 months 1 day
Aggregate Intrinsic Value of In-The-Money Options
Outstanding, end of period | $	$ 32,958,101	$ 32,958,101
Vested and expected to vest, end of period | $	32,492,850	32,492,850
Exercisable, end of period | $	$ 28,597,666	$ 28,597,666