Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Supplemental Schedule of Noncash Investing and Financing Activities
Cash dividends declared, but not yet paid		$ 4.2
Assets acquired, net of cash	$ 98.9	321.6
Liabilities assumed	$ 7.0	$ 59.2