Income Taxes - Components of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Accrued expenses	$ 1.9	$ 0.7
Accounts receivable	1.0	0.6
Net operating loss carryforward	16.4	20.5
Stock-based compensation	1.1	1.2
Credits	0.1	0.1
Lease obligations	10.1	12.6
Other comprehensive income	0.4
Other	0.6	0.6
Total deferred tax assets	31.6	36.3
Valuation allowance	(1.7)
Net deferred tax assets	29.9	36.3
Deferred tax liabilities:
Intangible assets	(69.1)	(65.7)
Property and equipment	(7.2)	(4.0)
Lease assets	(8.4)	(10.9)
Other	(0.2)
Total deferred tax liabilities	(84.9)	(80.6)
Net deferred tax liabilities	$ (55.0)	$ (44.3)