Income Tax - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Loss Carryforwards [Line Items]
Tax credit carryforwards	$ 4.8
Increase of liability for an uncertain tax position		$ 1.9
Income taxes, net of refunds	21.3	$ 6.8	$ 36.0
Federal
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	85.2
State
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 3.1