Acquisitions and Divestitures - 2017 Purchase Price Allocation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Cash paid for acquisition of businesses, net of cash acquired	$ 0.0	$ 21.3	$ 120.7
Acquisitions 2017
Business Acquisition [Line Items]
Cash paid for acquisition of businesses, net of cash acquired			108.2
Cash and cash equivalents			4.5
Amounts due to sellers			0.7
Non-monetary consideration			4.2
Estimated purchase price			117.6
Assets acquired:
Cash and cash equivalents			4.5
Property and equipment			10.6
Goodwill and identifiable intangible assets			105.2
Other current and long-term assets			10.2
Liabilities assumed:
Accrued expenses and other current liabilities			(3.7)
Long-term liabilities and deferred tax liabilities			(9.1)
Purchase price			$ 117.6