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Securities, HTM Securities in Continuous Unrealized Loss Position (Details) $ in Thousands | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2021 USD ($) Position | Dec. 31, 2020 USD ($) Position
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 151,842 | $ 103,147
12 months or longer | 0 | 0
Total | 151,842 | 103,147
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (4,219) | (1,675)
12 months or longer | 0 | 0
Total | $ (4,219) | $ (1,675)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 43 | 9
12 months or longer | Position | 0 | 0
Total | Position | 43 | 9
HTM debt securities | $ 622,351 | $ 616,560
Accrued interest reversed against interest income | 0 | 0
Collateral-dependent HTM debt securities | 0 | 0
AIR on HTM debt securities | 2,600 | 2,700
Past Due [Member] |  |
Unrealized Loss Position, Number of Positions [Abstract] |  |
HTM debt securities | 0 | 0
Federal Agency [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | 96,707 | 98,342
12 months or longer | 0 | 0
Total | 96,707 | 98,342
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (3,293) | (1,658)
12 months or longer | 0 | 0
Total | $ (3,293) | $ (1,658)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 4 | 4
12 months or longer | Position | 0 | 0
Total | Position | 4 | 4
HTM debt securities | $ 100,000 | $ 100,000
Mortgage-Backed [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | 7,710 |
12 months or longer | 0 |
Total | 7,710 |
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (38) |
12 months or longer | 0 |
Total | $ (38) |
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 1 |
12 months or longer | Position | 0 |
Total | Position | 1 |
State & Municipal [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 47,425 | 4,805
12 months or longer | 0 | 0
Total | 47,425 | 4,805
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (888) | (17)
12 months or longer | 0 | 0
Total | $ (888) | $ (17)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 38 | 5
12 months or longer | Position | 0 | 0
Total | Position | 38 | 5
HTM debt securities | $ 275,002 | $ 214,863
US Government Agencies Debt Securities and US Government-sponsored Enterprises Debt Securities [Member] |  |
Unrealized Loss Position, Number of Positions [Abstract] |  |
Held-to-maturity debt securities, percentage | 56.00% | 65.00%

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