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Mortgage Banking Activities, Components of Loans Held For Sale (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Schedule of Residential Mortgage Loans Held For Sale [Line Items] |  |  |
Number of days for past due for a residential mortgage loan to be considered nonperforming (in days) | 90 days | 90 days |
Residential mortgage loans held for sale, nonperforming | $ 0 | $ 0 |
Credit losses recognized on residential mortgage loans held for sale | 0 | 0 | $ 0
Components of Residential Mortgage Loans Held for Sale [Abstract] |  |  |
Unpaid principal balance | 175,117 | 145,057 |
Residential mortgage loans held for sale, Fair value | 177,703 | 146,971 |
Residential mortgage loans held for sale | $ 182,271 | $ 149,221 |
Not Designated as Hedging Instrument [Member] | Residential mortgage loan commitments [Member] |  |  |
Schedule of Residential Mortgage Loans Held For Sale [Line Items] |  |  |
General number of days outstanding for residential mortgage commitments, minimum (in days) | 60 days | 60 days |
General number of days outstanding for residential mortgage commitments, maximum (in days) | 90 days | 90 days |
Components of Residential Mortgage Loans Held for Sale [Abstract] |  |  |
Derivative, Notional Amount | $ 158,460 | $ 160,848 |
Derivative, Net fair value | $ 5,233 | $ 5,378 |
Not Designated as Hedging Instrument [Member] | Forward sales contracts [Member] |  |  |
Schedule of Residential Mortgage Loans Held For Sale [Line Items] |  |  |
General number of days for delivery of loans, for which the price is set by forward sales contracts, minimum (in days) | 60 days | 60 days |
General number of days for delivery of loans, for which the price is set by forward sales contracts, maximum (in days) | 90 days | 90 days |
Components of Residential Mortgage Loans Held for Sale [Abstract] |  |  |
Derivative, Notional Amount | $ 315,203 | $ 274,000 |
Derivative, Net fair value | $ (665) | $ (3,128) |

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- Definition Fair value of the assets less the liabilities of a derivative or group of derivatives. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611 + Details
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- Definition Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522 + Details
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