Regulatory Capital and Other Regulatory Matters - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Capital Requirements on Foreign Financial Institutions [Line Items]
Assets	$ 109,920	$ 97,015
Brazil [Member]
Capital Requirements on Foreign Financial Institutions [Line Items]
Capital ratio	19.10%
Capital requirement	10.50%
International Regulated Bank And Finance Companies [Member]
Capital Requirements on Foreign Financial Institutions [Line Items]
Assets	$ 7,900	$ 7,800

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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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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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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Total Capital divided by risk weighted assets as defined in the regulations.

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