Indebtedness - Schedule of Notes Maturity (Details) - Unsecured Senior Notes	Mar. 31, 2020 USD ($)
Debt Instrument [Line Items]
2020	$ 0
2021	0
2022	0
2023	950,000,000
2024	0
Thereafter	1,350,000,000
Total unsecured senior notes principal amount	$ 2,300,000,000

Face (par) amount of debt instrument at time of issuance.

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