| **General (Details) - Estimated - One-time cumulative-effect adjustment $ in Millions** | Jan. 01, 2020 USD ($) |
|-----------------------------------------------------------------------------------------|-----------------------|
| **New Accounting Pronouncements or Change in Accounting Principle [Line Items]**        |                  |
| Life of loan portfolio                                                                  | 4 years               |
| Reserve for potential losses from unfunded commitments                                  | $ 18                  |
| Minimum                                                                                 |                  |
| **New Accounting Pronouncements or Change in Accounting Principle [Line Items]**        |                  |
| Increase in allowance                                                                   | 55.00%                |
| Maximum                                                                                 |                  |
| **New Accounting Pronouncements or Change in Accounting Principle [Line Items]**        |                  |
| Increase in allowance                                                                   | 65.00%                |

| X                                                                                                                                                                                                                                                                 |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Allowance for Credit Loss, Increase, Percent
+ References
No definition available.
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| X                                                                                                                                                                                                                         |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Loan Portfolio, Term
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
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| - Definition
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.
+ References
No definition available.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.
+ References
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| X                                                                                                                                            |
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| X                                                                                                                       |
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