Fair Value Measurements (Details) $ in Millions	6 Months Ended
Jun. 30, 2019 USD ($)
Financial Liabilities
Transfer of assets from level 1 to level 2	$ 0.0
Transfer of assets from level 2 to level 1	0.0
Transfer of liabilities from level 1 to level 2	0.0
Transfer of liabilities from level 2 to level 1	0.0
Transfer of assets into level 3	0.0
Transfer of assets out of level 3	0.0
Transfer of liabilities into level 3	0.0
Transfer of liabilities out of level 3	0.0
Recurring
Financial Liabilities
Long-term debt	2,195.3
Total	2,218.3
Recurring \| Interest rate swaps
Financial Liabilities
Interest rate swaps	23.0
Significant other observable inputs (Level 2) \| Recurring
Financial Liabilities
Long-term debt	2,195.3
Total	2,218.3
Significant other observable inputs (Level 2) \| Recurring \| Interest rate swaps
Financial Liabilities
Interest rate swaps	$ 23.0

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value of financial and nonfinancial obligations.

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