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Debt Securities - Narrative (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2021 USD ($) security | Dec. 31, 2020 USD ($)
Summary of debt securities |  |
Debt securities pledged as collateral | $ 2,687,652,000 | $ 2,169,967,000
Severity rate on available-for-sale debt securities in an unrealized loss position | 5.00% |
Number of credit rating categories, highest | security | 4 |
Debt securities, available-for-sale | $ 9,170,849,000 | 5,337,814,000
Interest receivable, available-for-sale debt securities | 18,788,000 | 20,215,000
ACL on available-for-sale debt securities | 0 |
Interest receivable, held-to-maturity debt securities | 8,737,000 | 1,728,000
ACL on held-to-maturity debt securities | 0 |
Financial Asset, Past Due |  |
Summary of debt securities |  |
Debt securities, available-for-sale | 0 | 0
Debt securities, held-to-maturity | $ 0 | $ 0

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- Definition Amount excluding accrued interest, of allowance for credit loss 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 + Details
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- Definition Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (b)(1)(i) -URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728 + Details
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