Non-U.S. Activities - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Total assets	$ 323,139	$ 314,706
Non-U.S.
Segment Reporting Information [Line Items]
Total assets	$ 96,280	$ 92,330

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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+ Details