Goodwill (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Goodwill [Line Items]
Goodwill	$ 458	$ 458	$ 458
Accumulated impairment loss	1,819		$ 1,819
Goodwill impairment charge	$ 0	784
Wealth and Personal Banking [Member]
Goodwill [Line Items]
Goodwill impairment charge		$ 784

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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