Financing Arrangements - Narrative (Details) - USD ($)		3 Months Ended	9 Months Ended
May 13, 2020	Sep. 30, 2020	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Fair value of debt instruments		$ 1,940,600,000	$ 1,940,600,000	$ 1,271,800,000
Senior Notes \| 5.75% Senior Notes Due 2025
Debt Instrument [Line Items]
Aggregate prinicipal	$ 650,000,000
Interest rate, stated percentage	5.75%	5.75%	5.75%
Proceeds from Notes offering, net of debt issuance costs	$ 640,500,000
Debt related commitment fees		$ 9,600,000	$ 10,100,000

Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Represents the charge against earnings during the period for commitment fees and debt issuance expenses.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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