Income Taxes (Tables)

3 Months Ended

Mar. 31, 2018

Income Tax Disclosure [Abstract]

Roll-Forward of Unrecognized Tax Benefits

A roll-forward of unrecognized tax benefits is as follows:

(in millions)	March 31, 2018		December 31, 2017
Opening balance at January 1	$	2.2	$	2.2
Additions for tax positions of prior periods		0.4		0.5
Reductions due to lapsed statute of limitations		0.0		(0.5	)
Closing balance	$	2.6	$	2.2