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Loans Loans - Revolving Loans Converted to Term (Details) - Revolving Loans Converted to Term [Member] - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Remaining Revolving Loans Converted to Term During Period | $ 23,920 | $ 89,546
Commercial Portfolio Segment [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Remaining Revolving Loans Converted to Term During Period | 10,224 | 25,340
Commercial and Industrial Total Energy Loans [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Remaining Revolving Loans Converted to Term During Period | 7,144 | 38,642
Commercial Real Estate Buildings Land And Other Loans [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Remaining Revolving Loans Converted to Term During Period | 637 | 8,094
Construction Loans [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Remaining Revolving Loans Converted to Term During Period | 0 | 0
Total consumer real estate loans [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Remaining Revolving Loans Converted to Term During Period | 421 | 2,132
Consumer Loan [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Remaining Revolving Loans Converted to Term During Period | $ 5,494 | $ 15,338

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