Indebtedness - Schedule of Notes Maturity (Details) - Unsecured Senior Notes - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
2021 through 2025	$ 0
Thereafter	2,100
Total unsecured senior notes principal amount	$ 2,100	$ 2,398

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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