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v3.23.3

Securities, Held to Maturity (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |  |  |
Amortized cost | $ 914,520 |  | $ 914,520 |  | $ 919,517
Unrealized gains | 0 |  | 0 |  | 209
Unrealized losses | (130,534) |  | (130,534) |  | (107,079)
Estimated fair value | 783,986 |  | 783,986 |  | 812,647
Allowance for credit losses on HTM securities | 0 |  | 0 |  | 0
Transactions of HTM securities [Abstract] |  |  |  |  |
Gains from calls on HTM securities | 0 | $ 0 | 0 | $ 4 |
Asset Pledged as Collateral [Member] | Public Deposits or Other Purposes [Member] |  |  |  |  |
Securities pledged [Abstract] |  |  |  |  |
AFS and HTM securities | 1,990,000 |  | 1,990,000 |  | 1,730,000
Asset Pledged as Collateral [Member] | Securities Sold under Repurchase Agreements [Member] |  |  |  |  |
Securities pledged [Abstract] |  |  |  |  |
AFS and HTM securities | 157,400 |  | 157,400 |  | 149,500
Federal Agency [Member] |  |  |  |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |  |  |
Amortized cost | 100,000 |  | 100,000 |  | 100,000
Unrealized gains | 0 |  | 0 |  | 0
Unrealized losses | (23,003) |  | (23,003) |  | (20,678)
Estimated fair value | 76,997 |  | 76,997 |  | 79,322
Mortgage-Backed, Government Sponsored Enterprises [Member] |  |  |  |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |  |  |
Amortized cost | 233,580 |  | 233,580 |  | 249,511
Unrealized gains | 0 |  | 0 |  | 0
Unrealized losses | (45,066) |  | (45,066) |  | (36,819)
Estimated fair value | 188,514 |  | 188,514 |  | 212,692
Mortgage-Backed, U.S. Government Agency Securities [Member] |  |  |  |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |  |  |
Amortized cost | 17,094 |  | 17,094 |  | 18,396
Unrealized gains | 0 |  | 0 |  | 4
Unrealized losses | (1,328) |  | (1,328) |  | (619)
Estimated fair value | 15,766 |  | 15,766 |  | 17,781
Collateralized Mortgage Obligations, Government-Sponsored Enterprises [Member] |  |  |  |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |  |  |
Amortized cost | 192,243 |  | 192,243 |  | 207,738
Unrealized gains | 0 |  | 0 |  | 200
Unrealized losses | (18,562) |  | (18,562) |  | (14,876)
Estimated fair value | 173,681 |  | 173,681 |  | 193,062
Collateralized Mortgage Obligations, U.S. Government Agency Securities [Member] |  |  |  |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |  |  |
Amortized cost | 64,537 |  | 64,537 |  | 66,628
Unrealized gains | 0 |  | 0 |  | 0
Unrealized losses | (13,259) |  | (13,259) |  | (9,842)
Estimated fair value | 51,278 |  | 51,278 |  | 56,786
State & Municipal [Member] |  |  |  |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |  |  |
Amortized cost | 307,066 |  | 307,066 |  | 277,244
Unrealized gains | 0 |  | 0 |  | 5
Unrealized losses | (29,316) |  | (29,316) |  | (24,245)
Estimated fair value | $ 277,750 |  | $ 277,750 |  | $ 253,004

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