Components of Provision (Benefit) for Income Taxes (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current:
Federal		$ 7.0	$ 6.6	$ 3.0
Foreign		0.6	0.0	0.3
State and local		2.0	1.8	1.3
Current, Total		9.6	8.4	4.6
Deferred:
Federal		8.4	25.4	17.8
Foreign		(0.7)	(2.0)	(3.0)
State and local		0.1	2.3	4.3
Deferred Income Tax Expense Benefit Continuing Operations		7.8	25.7	19.1
Total income tax provision	$ (1.4)	$ 17.4	$ 34.1	$ 23.7

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Amount of deferred federal income tax expense (benefit) pertaining to income (loss) from continuing operations.

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