Financing - Schedule of Contractual Maturities of Debt (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total principal payments	$ 1,800.0	$ 24.6
Unsecured Debt
Debt Instrument [Line Items]
2021	0.0
2022	1,000.0
2023	800.0
2024	0.0
2025	0.0
Thereafter	0.0
Total principal payments	$ 1,800.0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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