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v3.24.1.u1

Securities, Held to Maturity (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |
Amortized cost | $ 890,863 |  | $ 905,267
Unrealized gains | 101 |  | 271
Unrealized losses | (97,645) |  | (91,014)
Estimated fair value | 793,319 |  | 814,524
Transactions of HTM securities [Abstract] |  |  |
Gains from calls on HTM securities | 0 | $ 0 |
Asset Pledged as Collateral [Member] | Public Deposits or Other Purposes [Member] |  |  |
Securities pledged [Abstract] |  |  |
AFS and HTM securities | 1,990,000 |  | 2,030,000
Asset Pledged as Collateral [Member] | Securities Sold under Repurchase Agreements [Member] |  |  |
Securities pledged [Abstract] |  |  |
AFS and HTM securities | 159,300 |  | 177,200
Federal Agency [Member] |  |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |
Amortized cost | 100,000 |  | 100,000
Unrealized gains | 0 |  | 0
Unrealized losses | (18,440) |  | (17,784)
Estimated fair value | 81,560 |  | 82,216
Mortgage-Backed, Government Sponsored Enterprises [Member] |  |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |
Amortized cost | 224,344 |  | 228,720
Unrealized gains | 0 |  | 0
Unrealized losses | (34,187) |  | (31,613)
Estimated fair value | 190,157 |  | 197,107
Mortgage-Backed, U.S. Government Agency Securities [Member] |  |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |
Amortized cost | 16,742 |  | 17,086
Unrealized gains | 2 |  | 3
Unrealized losses | (736) |  | (566)
Estimated fair value | 16,008 |  | 16,523
Collateralized Mortgage Obligations, Government-Sponsored Enterprises [Member] |  |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |
Amortized cost | 182,813 |  | 187,457
Unrealized gains | 0 |  | 57
Unrealized losses | (13,466) |  | (12,021)
Estimated fair value | 169,347 |  | 175,493
Collateralized Mortgage Obligations, U.S. Government Agency Securities [Member] |  |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |
Amortized cost | 63,137 |  | 63,878
Unrealized gains | 0 |  | 0
Unrealized losses | (11,206) |  | (10,908)
Estimated fair value | 51,931 |  | 52,970
State & Municipal [Member] |  |  |
Held-to-maturity securities, fair value to amortized cost [Abstract] |  |  |
Amortized cost | 303,827 |  | 308,126
Unrealized gains | 99 |  | 211
Unrealized losses | (19,610) |  | (18,122)
Estimated fair value | $ 284,316 |  | $ 290,215

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