Stock-Based Compensation - Restricted Stock Activity (Details) - Shares underlying unvested restricted stock units	3 Months Ended
	Mar. 31, 2020 $ / shares shares
Restricted Stock Units Outstanding
Beginning unvested balance (shares) | shares	496,131
Granted (shares) | shares	14,548
Vested (shares) | shares	(5,594)
Canceled (shares) | shares	(16,164)
Ending unvested balance (shares) | shares	488,921
Weighted-Average Grant Date Fair Value
Beginning balance of options outstanding (in usd per share) | $ / shares	$ 82.08
Granted (unaudited) (in usd per share) | $ / shares	85.30
Vested (unaudited) (in usd per share) | $ / shares	67.81
Canceled (unaudited) (in usd per share) | $ / shares	71.97
Ending balance of options outstanding (in usd per share) | $ / shares	$ 82.67