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Securities, AFS Securities in Continuous Unrealized Loss Position (Details) $ in Thousands | Jun. 30, 2021 USD ($) Position | Dec. 31, 2020 USD ($) Position
--- | --- | ---
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 654,971 | $ 213,643
12 months or longer | 1,194 | 800
Total | 656,165 | 214,443
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (8,534) | (2,170)
12 months or longer | (9) | (9)
Total | $ (8,543) | $ (2,179)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 75 | 19
12 months or longer | Position | 5 | 4
Total | Position | 80 | 23
AIR on AFS debt securities | $ 3,500 | $ 3,300
Federal Agency [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | 243,660 | 148,537
12 months or longer | 0 | 0
Total | 243,660 | 148,537
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (4,810) | (2,052)
12 months or longer | 0 | 0
Total | $ (4,810) | $ (2,052)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 16 | 10
12 months or longer | Position | 0 | 0
Total | Position | 16 | 10
State & Municipal [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 42,038 |
12 months or longer | 0 |
Total | 42,038 |
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (480) |
12 months or longer | 0 |
Total | $ (480) |
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 27 |
12 months or longer | Position | 0 |
Total | Position | 27 |
Mortgage-Backed [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 250,767 | $ 47,269
12 months or longer | 774 | 800
Total | 251,541 | 48,069
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (2,472) | (60)
12 months or longer | (8) | (9)
Total | $ (2,480) | $ (69)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 17 | 3
12 months or longer | Position | 4 | 4
Total | Position | 21 | 7
Collateralized Mortgage Obligations [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 118,506 | $ 17,837
12 months or longer | 420 | 0
Total | 118,926 | 17,837
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (772) | (58)
12 months or longer | (1) | 0
Total | $ (773) | $ (58)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 15 | 6
12 months or longer | Position | 1 | 0
Total | Position | 16 | 6

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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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