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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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No definition available.

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Weighted average interest rate of debt outstanding.

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Fair value of the amount outstanding under the credit facility.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Debt - Schedule of Debt Instruments (Details) - USD ($) $ in Millions			12 Months Ended
	Nov. 18, 2019	Nov. 17, 2019	Dec. 31, 2019	Dec. 31, 2018	Jul. 15, 2019
Debt Instrument [Line Items]
Short-term debt			$ 195.0	$ 160.0
Long-term debt, net			2,222.1	2,149.6
Debt issuance costs			(27.1)	(20.4)
Total debt, net			$ 2,417.1	$ 2,309.6
Weighted average cost of debt			4.50%	5.10%
Term loan, due 2026
Debt Instrument [Line Items]
Maturity date	Nov. 18, 2026
Term loan, due 2024
Debt Instrument [Line Items]
Maturity date		Mar. 16, 2024
Secured debt \| Term loan, due 2026
Debt Instrument [Line Items]
Maturity date			Nov. 18, 2026
Long-term debt, net			$ 597.5
Secured debt \| Term loan, due 2024
Debt Instrument [Line Items]
Maturity date				Mar. 16, 2024
Long-term debt, net				$ 668.1
Senior unsecured notes
Debt Instrument [Line Items]
Long-term debt, net			$ 1,651.7	$ 1,501.9
Senior unsecured notes \| 5.250% senior unsecured notes, due 2022
Debt Instrument [Line Items]
Maturity date			Jan. 31, 2022	Jan. 31, 2022
Debt interest rate percentage			5.25%	5.25%	5.25%
Long-term debt, net			$ 0.0	$ 549.7
Senior unsecured notes \| 5.625% senior unsecured notes, due 2024
Debt Instrument [Line Items]
Maturity date			Jan. 31, 2024	Jan. 31, 2024
Debt interest rate percentage			5.625%	5.625%
Long-term debt, net			$ 501.7	$ 502.2
Senior unsecured notes \| 5.875% senior unsecured notes, due 2025
Debt Instrument [Line Items]
Maturity date			Mar. 15, 2025	Mar. 15, 2025
Debt interest rate percentage			5.875%	5.875%
Long-term debt, net			$ 0.0	$ 450.0
Senior unsecured notes \| 5.000% senior unsecured notes, due 2027
Debt Instrument [Line Items]
Maturity date			Aug. 15, 2027
Debt interest rate percentage			5.00%		5.00%
Long-term debt, net					$ 650.0
Senior unsecured notes \| 4.625% senior unsecured notes, due 2030
Debt Instrument [Line Items]
Maturity date			Mar. 15, 2030
Debt interest rate percentage	4.625%		4.625%
Long-term debt, net	$ 500.0
Short-term debt \| AR Facility
Debt Instrument [Line Items]
Credit facility borrowings			$ 105.0	85.0
Short-term debt \| Repurchase Facility
Debt Instrument [Line Items]
Credit facility borrowings			90.0	75.0
Long-term debt \| Senior unsecured notes \| 5.000% senior unsecured notes, due 2027
Debt Instrument [Line Items]
Long-term debt, net			650.0	$ 0.0
Long-term debt \| Senior unsecured notes \| 4.625% senior unsecured notes, due 2030
Debt Instrument [Line Items]
Long-term debt, net			$ 500.0