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Debt Securities Available-for-Sale - Gross Unrealized Losses on Mortgage-Backed Securities (Details) - USD ($) $ in Thousands | Jun. 30, 2022 | Dec. 31, 2021
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Debt Securities, Available-for-sale [Line Items] |  |
Unrealized losses, less than 12 months | $ (37,689) | $ (4,637)
Estimated fair value, less than 12 months | 970,107 | 689,869
Unrealized losses, 12 months or more | (5,898) | (466)
Estimated fair value, 12 months or more | 83,588 | 21,328
Unrealized losses, total | (43,587) | (5,103)
Estimated fair value, total | 1,053,695 | 711,197
U.S. Government agency securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Unrealized losses, less than 12 months | (1,642) | 0
Estimated fair value, less than 12 months | 73,358 | 0
Unrealized losses, 12 months or more | (127) | (54)
Estimated fair value, 12 months or more | 1,444 | 2,290
Unrealized losses, total | (1,769) | (54)
Estimated fair value, total | 74,802 | 2,290
GSE | Pass-through Certificates |  |
Debt Securities, Available-for-sale [Line Items] |  |
Unrealized losses, less than 12 months | (24,602) | (2,543)
Estimated fair value, less than 12 months | 490,569 | 417,291
Unrealized losses, 12 months or more | (668) | (318)
Estimated fair value, 12 months or more | 7,927 | 14,625
Unrealized losses, total | (25,270) | (2,861)
Estimated fair value, total | 498,496 | 431,916
GSE | Real estate mortgage investment conduits (REMICs) |  |
Debt Securities, Available-for-sale [Line Items] |  |
Unrealized losses, less than 12 months | (6,077) | (1,350)
Estimated fair value, less than 12 months | 246,515 | 125,725
Unrealized losses, 12 months or more | (3,405) | (94)
Estimated fair value, 12 months or more | 60,905 | 4,413
Unrealized losses, total | (9,482) | (1,444)
Estimated fair value, total | 307,420 | 130,138
Corporate bonds | Other debt securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Unrealized losses, less than 12 months | (5,368) | (744)
Estimated fair value, less than 12 months | 159,665 | 146,853
Unrealized losses, 12 months or more | (1,698) | 0
Estimated fair value, 12 months or more | 13,312 | 0
Unrealized losses, total | (7,066) | (744)
Estimated fair value, total | $ 172,977 | $ 146,853

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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=124269663&loc=SL82922890-210455 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27337-111563 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 55 -Paragraph 8 -URI https://asc.fasb.org/extlink&oid=121590138&loc=SL82922954-210456 + Details
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=124269663&loc=SL82922890-210455 + Details
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