Notes Payable and Indebtedness - Maturities and Interest Payments (Details) $ in Millions	Jun. 30, 2020 USD ($)
Rest of 2020
Principal	$ 312.7
Interest	110.0
Total Debt	422.7
2021
Principal	25.3
Interest	195.0
Total Debt	220.3
2022
Principal	25.3
Interest	194.1
Total Debt	219.4
2023
Principal	25.3
Interest	193.1
Total Debt	218.4
2024
Principal	112.8
Interest	189.5
Total Debt	302.3
Thereafter
Principal	3,559.8
Interest	315.3
Total Debt	3,875.1
Total
Principal amount, long-term debt	4,061.2
Interest	1,197.0
Total Debt	$ 5,258.2

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