Derivative instruments (Narrative) (Detail) $ in Billions	3 Months Ended
Jun. 30, 2020 USD ($)
Disclosure Of Derivative Instruments [Line Items]
Increase (decrease) in derivative financial assets	$ (61)
Increase (decrease) in derivative financial liabilities	$ (54)

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

No definition available.

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