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Mortgage Banking Derivatives (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Mortgage Banking Derivatives |  |  |
Amount of loans sold to investors | $ 384,400 |  |
Proceeds from sale of loan to investors | 388,538 | $ 168,472 | $ 137,622
Gain on sale of loan | 15,519 | 5,112 | $ 3,791
Federal National Mortgage Association [Member] |  |  |
Mortgage Banking Derivatives |  |  |
Amount of loans sold to investors | $ 312,000 |  |
Federal National Mortgage Association [Member] | Customer Concentration Risk [Member] |  |  |
Mortgage Banking Derivatives |  |  |
Percentage of concentration risk | 83.20% |  |
Federal Home Loan Mortgage Corporation [Member] |  |  |
Mortgage Banking Derivatives |  |  |
Amount of loans sold to investors | $ 44,200 |  |
Federal Home Loan Mortgage Corporation [Member] | Customer Concentration Risk [Member] |  |  |
Mortgage Banking Derivatives |  |  |
Percentage of concentration risk | 11.80% |  |
Not Designated as Hedging Instrument [Member] | Forward Contracts [Member] |  |  |
Mortgage Banking Derivatives |  |  |
Notional or Contractual Amount | $ 46,500 | 13,500 |
Fair value | (228) | (15) |
Not Designated as Hedging Instrument [Member] | Interest Rate Lock Commitments [Member] |  |  |
Mortgage Banking Derivatives |  |  |
Notional or Contractual Amount | 37,972 | 10,167 |
Fair value | $ 1,068 | $ 265 |

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- Definition The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 310 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121581245&loc=d3e21310-158488 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 310 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121581245&loc=d3e21286-158488 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 310 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=117337389&loc=d3e21493-158490 + Details
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