Financial Instruments and Fair Value Measurements Fair Value of Financial Instruments (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unrealized Gain (Loss) on Interest Rate Cash Flow Hedges, Pretax, Accumulated Other Comprehensive Income (Loss)			$ (5.0)
Interest Rate Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net			(1.2)
Long-Term Debt, Excluding Capital Leases and Note Issuance Costs, Net	[1]		1,880.0	$ 1,687.1
Financing Arrangement Liability			44.6	0.0
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-Term Debt, Excluding Capital Leases and Note Issuance Costs, Net	[1]		1,673.6	1,687.5
Financing Arrangement Liability			43.6	$ 0.0
Interest Rate Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative, Notional Amount			$ 300.0
Derivative, Average Fixed Interest Rate			2.938%
Interest Rate Contract [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest Rate Cash Flow Hedge Derivative at Fair Value, Net			$ 5.0
Interest Rate Cash Flow Hedge Asset at Fair Value			3.8
Interest Rate Cash Flow Hedge Liability at Fair Value			1.2
Interest Rate Contract [Member] | Quoted Prices in active markets Level 1 | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest Rate Cash Flow Hedge Asset at Fair Value			0.0
Interest Rate Cash Flow Hedge Liability at Fair Value			0.0
Interest Rate Contract [Member] | Significant observable inputs Level 2 | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest Rate Cash Flow Hedge Asset at Fair Value			3.8
Interest Rate Cash Flow Hedge Liability at Fair Value			1.2
Interest Rate Contract [Member] | Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest Rate Cash Flow Hedge Asset at Fair Value			0.0
Interest Rate Cash Flow Hedge Liability at Fair Value			$ 0.0
Scenario, Forecast [Member] | Interest Rate Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months		$ 1.2

[1] *Excludes capital leases and note issuance costs.