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Debt Securities Available-for-Sale - Gross Unrealized Losses On Mortgage-Backed Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
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Schedule of Available-for-sale Securities [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (4,637) | $ (719)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 689,869 | 242,146
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (466) | (11)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 21,328 | 459
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total | (5,103) | (730)
Debt Securities, Available-for-sale, Unrealized Loss Position | 711,197 | 242,605
U.S. Government agency securities |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 0 | (10)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 0 | 3,158
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (54) | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 2,290 | 0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total | (54) | (10)
Debt Securities, Available-for-sale, Unrealized Loss Position | 2,290 | 3,158
Pass-through certificates | GSE |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (2,543) | (233)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 417,291 | 28,419
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (318) | (11)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 14,625 | 459
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total | (2,861) | (244)
Debt Securities, Available-for-sale, Unrealized Loss Position | 431,916 | 28,878
REMICs | GSE |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (1,350) | (476)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 125,725 | 210,569
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (94) | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 4,413 | 0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total | (1,444) | (476)
Debt Securities, Available-for-sale, Unrealized Loss Position | 130,138 | $ 210,569
Other debt securities | Corporate bonds |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (744) |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 146,853 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 0 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 0 |
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total | (744) |
Debt Securities, Available-for-sale, Unrealized Loss Position | $ 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 http://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 http://asc.fasb.org/extlink&oid=123581744&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 http://asc.fasb.org/extlink&oid=121590138&loc=SL82922954-210456 + Details
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