Long-Term Debt - Swap Agreements in the Balance Sheets (Unaudited) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member] \| Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	$ 48.4	$ 21.9

Fair value, before 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 elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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-Name Accounting Standards Codification
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Balance Type:	credit
Period Type:	instant