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Stockholders' Equity - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Oct. 01, 2018	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares authorized (in shares)	120,000,000		120,000,000	120,000,000.0	90,000,000.0
Common stock, shares issued (in shares)	64,564,526		64,222,603
Common stock, shares outstanding (in shares)	64,564,526		64,222,603
Preferred Stock, shares authorized (in shares)	10,000,000.0
Preferred Stock, shares issued (in shares)	0		0
Preferred Stock, shares outstanding (in shares)	0		0
Compensation expense	$ 3.3	$ 3.5
Unrecognized compensation cost	$ 29.7
Weighted average remaining period	3 years
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value of stock awards	$ 16.8
2014 Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock available for delivery pursuant to the grant of awards (in shares)	1,500,000
2014 Plan [Member] \| Restricted Shares and Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares for vesting period	5 years