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Mortgage Banking Activities, Components of Loans Held For Sale (Details) - USD ($) $ in Thousands | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2020 | Jun. 30, 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 | 285,274 |  | 175,117
Residential mortgage loans held for sale, Fair value | 296,445 |  | 177,703
Residential mortgage loans held for sale | $ 319,357 |  | $ 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 | $ 546,304 |  | $ 158,460
Derivative, Net fair value | $ 27,631 |  | $ 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 | $ 825,775 |  | $ 315,203
Derivative, Net fair value | $ (4,719) |  | $ (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 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=121572278&loc=d3e13433-108611 + Details
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- Definition Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security. + 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=121593590&loc=d3e4428-111522 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 948 -SubTopic 310 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=120238483&loc=d3e48678-111004 + Details
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