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Debt Securities Available-for-Sale - Narrative (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2021 USD ($) security instrument | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Schedule of Available-for-sale Securities [Line Items] |  |  |
Carrying value of securities available-for-sale | $ 522,100 | $ 542,100 |
Gross proceeds on sales of securities | 328,966 | 23,628 | $ 79,255
Debt securities, available-for-sale, realized gain | 1,500 | 350 | 514
Debt securities, available-for-sale, realized loss | 0 | 23 | 0
Debt securities, trading, realized gain (loss) | 1,700 | $ 1,600 | $ 2,000
Accrued interest receivable associated with debt securities available-for-sale | $ 2,500 |  |
Continuous Unrealized Loss Position Less Than 12 Months | REMIC | Non-pass through certificates |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Number of debt securities, unrealized loss position less than 12 months | security | 28 |  |
GSE | REMIC |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Number of debt securities, unrealized loss position less than 12 months | instrument | 1 |  |
GSE | Continuous Unrealized Loss Position 12 Months Or Longer | REMIC |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Number of debt securities, unrealized loss position longer than 12 months | security | 20 |  |
GSE | Continuous Unrealized Loss Position 12 Months Or Longer | REMIC | Pass-through certificates |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Number of debt securities, unrealized loss position longer than 12 months | security | 15 |  |
GSE | Continuous Unrealized Loss Position Less Than 12 Months | REMIC | Pass-through certificates |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Number of debt securities, unrealized loss position less than 12 months | security | 27 |  |
Municipal Bonds | REMIC |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Number of debt securities, unrealized loss position less than 12 months | instrument | 21 |  |

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- Definition Amount, after allowance for credit loss, of accrued interest on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 3A -URI http://asc.fasb.org/extlink&oid=124269663&loc=SL120267853-210455 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2A -URI http://asc.fasb.org/extlink&oid=123581744&loc=SL121698322-111563 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 3B -URI http://asc.fasb.org/extlink&oid=124269663&loc=SL120267856-210455 + Details
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