Notes Payable and Indebtedness - Maturities and Interest Payments (Details) $ in Millions	Sep. 30, 2020 USD ($)
Fourth Quarter 2020
Principal	$ 6.3
Interest	24.5
Total Debt	30.8
2021
Principal	25.3
Interest	172.5
Total Debt	197.8
2022
Principal	25.3
Interest	171.5
Total Debt	196.8
2023
Principal	25.3
Interest	170.5
Total Debt	195.8
2024
Principal	25.3
Interest	169.6
Total Debt	194.9
Thereafter
Principal	3,279.9
Interest	276.5
Total Debt	3,556.4
Total
Principal amount, long-term debt	3,387.4
Interest	985.1
Total Debt	$ 4,372.5

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