Debt - Schedule of Debt Instruments (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Long-term debt, net	$ 2,621.9	$ 2,620.6
Total debt, net	$ 2,621.9	$ 2,620.6
Weighted average cost of debt	4.30%	4.30%
Secured debt \| Term loan, due 2026
Debt Instrument [Line Items]
Senior unsecured notes, due date	Nov. 18, 2026	Nov. 18, 2026
Senior unsecured notes \| 6.250% senior unsecured notes, due 2025
Debt Instrument [Line Items]
Stated interest rate	6.25%	6.25%
Senior unsecured notes, due date	Jun. 15, 2025	Jun. 15, 2025
Senior unsecured notes \| 5.000% senior unsecured notes, due 2027
Debt Instrument [Line Items]
Stated interest rate	5.00%	5.00%
Senior unsecured notes, due date	Aug. 15, 2027	Aug. 15, 2027
Senior unsecured notes \| Senior Notes Due 2029
Debt Instrument [Line Items]
Stated interest rate	4.25%	4.25%
Senior unsecured notes, due date	Jan. 15, 2029	Jan. 15, 2029
Senior unsecured notes \| 4.625% senior unsecured notes, due 2030
Debt Instrument [Line Items]
Stated interest rate	4.625%	4.625%
Senior unsecured notes, due date	Mar. 15, 2030	Mar. 15, 2030
Long-term debt
Debt Instrument [Line Items]
Debt issuance costs	$ (26.4)	$ (27.6)
Long-term debt \| Secured debt \| Term loan, due 2026
Debt Instrument [Line Items]
Long-term debt, net	598.3	598.2
Long-term debt \| Senior unsecured notes
Debt Instrument [Line Items]
Long-term debt, net	2,050.0	2,050.0
Long-term debt \| Senior unsecured notes \| 6.250% senior unsecured notes, due 2025
Debt Instrument [Line Items]
Long-term debt, net	400.0	400.0
Long-term debt \| Senior unsecured notes \| 5.000% senior unsecured notes, due 2027
Debt Instrument [Line Items]
Long-term debt, net	650.0	650.0
Long-term debt \| Senior unsecured notes \| Senior Notes Due 2029
Debt Instrument [Line Items]
Long-term debt, net	500.0	500.0
Long-term debt \| Senior unsecured notes \| 4.625% senior unsecured notes, due 2030
Debt Instrument [Line Items]
Long-term debt, net	$ 500.0	$ 500.0

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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Weighted average interest rate of debt outstanding.

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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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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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