Debt - Restricted Net Assets (Details) $ in Millions	Sep. 30, 2020 USD ($)
Senior Notes \| 4.98% Senior Notes, due March 2044
Debt Instrument [Line Items]
Amount of net assets restricted from transfer to parent company under different agreements	$ 2,200

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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