Credit Concentrations - Additional Information (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Concentration Risk [Line Items]
Cash deposits held at central banks	$ 117,300	$ 96,970
GS Bank USA [Member]
Concentration Risk [Line Items]
Cash deposits held at the Federal Reserve Bank of New York	$ 63,690	$ 50,550

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.

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