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Mortgage Servicing Rights - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Mortgage Loan Activity [Line Items] |  |  |
Sale of 1-4 family mortgage loans | $ 311,479 | $ 357,613 | $ 109,082
Total servicing portfolio | 841,700 | 718,200 | 509,200
Fannie Mae |  |  |
Mortgage Loan Activity [Line Items] |  |  |
Sale of 1-4 family mortgage loans | $ 287,900 | $ 345,100 | $ 94,500

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- Definition The cash inflow from sales of loans that are secured with real estate mortgages and are held with the intention to resell in the near future. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 21 -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3461-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3536-108585 + Details
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