Stock-Based Compensation - Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Options
Beginning balance (in shares)	588,024
Granted (in shares)	131,556
Exercised (in shares)	(11,440)
Canceled (in shares)	(3,531)
Ending balance (in shares)	704,609	588,024
Exercisable at period end (in shares)	448,375
Weighted Average Exercise Price
Beginning balance (in dollars per share)	$ 63.36
Granted (in dollars per share)	78.33
Exercised (in dollars per share)	37.84
Canceled (in dollars per share)	72.64
Ending balance (in dollars per share)	66.52	$ 63.36
Exercisable (in dollars per share)	$ 53.22
Weighted Average Remaining Contractual Life
Outstanding, weighted average remaining contractual life (in years)	6 years 3 months 18 days	5 years 8 months 12 days
Exercisable weighted average remaining contractual life (in years)	5 years 2 months 12 days
Aggregate Intrinsic Value
Beginning balance	$ 8.5
Granted
Exercised
Canceled
Ending balance	1.8	$ 8.5
Exercisable	$ 1.8

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Period Type:	instant

- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.