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Mortgage Banking Activities, Components of Loans Held For Sale (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019
Schedule of Residential Mortgage Loans Held For Sale [Line Items] |  |  |
Number of days for past due for 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 |
Components of Residential Mortgage Loans Held for Sale [Abstract] |  |  |
Unpaid principal balance | 185,713 |  | 175,117
Residential mortgage loans held for sale, Fair value | 191,860 |  | 177,703
Residential mortgage loans held for sale | $ 204,720 |  | $ 182,271
Residential Mortgage Loan Commitments [Member] | Not Designated as Hedging Instrument [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 | $ 657,570 |  | $ 158,460
Derivative, Net fair value | $ 24,250 |  | $ 5,233
Forward sales contracts [Member] | Not Designated as Hedging Instrument [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 for 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 | $ 750,719 |  | $ 315,203
Derivative, Net fair value | $ (11,390) |  | $ (665)

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- Definition Credit losses recognized on residential mortgage loans held for sale + References No definition available. + Details
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- Definition Represents the fair value of residential mortgage loans held for sale as of the balance sheet, exclusive of mortgage commitments and forward sales contracts + References No definition available. + Details
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- Definition Represents the minimum number of days from the point of pricing being set to delivery of forward sales contracts. + References No definition available. + Details
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- Definition Represents the number of days past due for residential mortgage loans held for sale to be reported as delinquent. + References No definition available. + Details
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- Definition Residential mortgage loans held for sale, 90 days past due or impaired. + References No definition available. + Details
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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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