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Debt Securities - Unrealized Loss Position (Details) $ in Thousands | Dec. 31, 2021 USD ($) security | Dec. 31, 2020 USD ($) security
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Debt Securities |  |
Number of securities | security | 263 | 46
Less than 12 months, fair value | $ 7,231,306 | $ 145,530
Less than 12 months, unrealized loss | (67,190) | (783)
12 months or more, fair value | 187,060 | 753
12 months or longer, unrealized loss | (5,501) | (9)
Total, fair value | 7,418,366 | 146,283
Total, unrealized loss | $ (72,691) | $ (792)
U.S. government and federal agency |  |
Debt Securities |  |
Number of securities | security | 50 | 18
Less than 12 months, fair value | $ 1,329,399 | $ 13,814
Less than 12 months, unrealized loss | (9,344) | (258)
12 months or more, fair value | 5,457 | 726
12 months or longer, unrealized loss | (252) | (9)
Total, fair value | 1,334,856 | 14,540
Total, unrealized loss | $ (9,596) | $ (267)
U.S. government sponsored enterprises |  |
Debt Securities |  |
Number of securities | security | 11 |
Less than 12 months, fair value | $ 239,928 |
Less than 12 months, unrealized loss | (996) |
12 months or more, fair value | 0 |
12 months or longer, unrealized loss | 0 |
Total, fair value | 239,928 |
Total, unrealized loss | $ (996) |
State and local governments |  |
Debt Securities |  |
Number of securities | security | 10 | 6
Less than 12 months, fair value | $ 11,080 | $ 3,121
Less than 12 months, unrealized loss | (83) | (54)
12 months or more, fair value | 1,760 | 0
12 months or longer, unrealized loss | (40) | 0
Total, fair value | 12,840 | 3,121
Total, unrealized loss | $ (123) | $ (54)
Corporate bonds |  |
Debt Securities |  |
Number of securities | security | 3 | 3
Less than 12 months, fair value | $ 12,483 | $ 5,500
Less than 12 months, unrealized loss | (17) | (8)
12 months or more, fair value | 0 | 0
12 months or longer, unrealized loss | 0 | 0
Total, fair value | 12,483 | 5,500
Total, unrealized loss | $ (17) | $ (8)
Residential mortgage-backed securities |  |
Debt Securities |  |
Number of securities | security | 151 | 14
Less than 12 months, fair value | $ 5,335,632 | $ 2,354
Less than 12 months, unrealized loss | (53,434) | (4)
12 months or more, fair value | 53,045 | 27
12 months or longer, unrealized loss | (832) | 0
Total, fair value | 5,388,677 | 2,381
Total, unrealized loss | $ (54,266) | $ (4)
Commercial mortgage-backed securities |  |
Debt Securities |  |
Number of securities | security | 38 | 5
Less than 12 months, fair value | $ 302,784 | $ 120,741
Less than 12 months, unrealized loss | (3,316) | (459)
12 months or more, fair value | 126,798 | 0
12 months or longer, unrealized loss | (4,377) | 0
Total, fair value | 429,582 | 120,741
Total, unrealized loss | $ (7,693) | $ (459)

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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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- 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 http://asc.fasb.org/extlink&oid=123581744&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 http://asc.fasb.org/extlink&oid=124269663&loc=SL82922890-210455 + Details
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