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Loans - Concentrations and Restrictions (Details) $ in Billions | 3 Months Ended
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Mar. 31, 2020 USD ($)
Consumer | Residential Real Estate |
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Concentration risk, percentage | 19.00%
Commercial | Finance And Insurance Companies |
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Financing receivable, before allowance for credit loss | $ 2.8
Percentage of commercial & industrial loan portfolio | 13.00%
Percentage contributed in total loan | 8.00%
Commercial | Loans to Mortgage Companies |
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Financing receivable, before allowance for credit loss | $ 5.7
Percentage of commercial & industrial loan portfolio | 26.00%
Percentage contributed in total loan | 17.00%
Commercial | Finance Insurance And Loans To Mortgage Companies |
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Percentage of commercial & industrial loan portfolio | 39.00%

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