Notes Payable and Indebtedness - Maturities and Interest Payments (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Remainder of 2021
Principal	$ 21.1
Interest	108.0
Total Debt	129.1
2022
Principal	28.1
Interest	168.2
Total Debt	196.3
2023
Principal	28.1
Interest	167.2
Total Debt	195.3
2024
Principal	28.1
Interest	166.3
Total Debt	194.4
2025
Principal	28.1
Interest	165.3
Total Debt	193.4
Thereafter
Principal	3,540.5
Interest	107.6
Total Debt	3,648.1
Total
Principal Amount	3,674.0	$ 3,381.0
Interest	882.6
Total Debt	$ 4,556.6

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