Securities - Gross Unrealized Losses and Fair Value by Investment Category (Details) $ in Thousands	Jun. 30, 2025 USD ($) security	Dec. 31, 2024 USD ($) security
Available for Sale:
Number of positions, Less than 12 Months \| security	148	16
Fair Value, Less than 12 Months	$ 559,090	$ 95,216
Unrealized Losses, Less than 12 Months	$ (6,102)	$ (1,120)
Number of positions, 12 Months or More \| security	115	122
Fair value, 12 Months or More	$ 590,175	$ 606,628
Unrealized Losses, 12 Months or More	$ (107,308)	$ (137,488)
Number of positions \| security	263	138
Fair Value	$ 1,149,265	$ 701,844
Unrealized Losses	$ (113,410)	$ (138,608)
Held to Maturity:
Number of positions, Less than 12 Months \| security	8	0
Fair Value, Less than 12 Months	$ 32,094	$ 0
Unrealized Losses, Less than 12 Months	$ (2,308)	$ 0
Number of positions, 12 Months or More \| security	223	235
Fair value, 12 Months or More	$ 952,045	$ 1,000,874
Unrealized Losses, 12 Months or More	$ (90,182)	$ (123,603)
Number of positions \| security	231	235
Fair Value	$ 984,139	$ 1,000,874
Unrealized Losses	$ (92,490)	$ (123,603)
Obligations of states and political subdivisions
Available for Sale:
Number of positions, Less than 12 Months \| security	107	0
Fair Value, Less than 12 Months	$ 114,704	$ 0
Unrealized Losses, Less than 12 Months	$ (2,434)	$ 0
Number of positions, 12 Months or More \| security	7	7
Fair value, 12 Months or More	$ 13,096	$ 12,841
Unrealized Losses, 12 Months or More	$ (1,923)	$ (2,269)
Number of positions \| security	114	7
Fair Value	$ 127,800	$ 12,841
Unrealized Losses	$ (4,357)	$ (2,269)
Held to Maturity:
Number of positions, Less than 12 Months \| security	7	0
Fair Value, Less than 12 Months	$ 16,490	$ 0
Unrealized Losses, Less than 12 Months	$ (1,671)	$ 0
Number of positions, 12 Months or More \| security	119	128
Fair value, 12 Months or More	$ 223,984	$ 240,394
Unrealized Losses, 12 Months or More	$ (39,090)	$ (42,491)
Number of positions \| security	126	128
Fair Value	$ 240,474	$ 240,394
Unrealized Losses	$ (40,761)	$ (42,491)
Other debt securities
Available for Sale:
Number of positions, Less than 12 Months \| security	11	2
Fair Value, Less than 12 Months	$ 104,255	$ 22,357
Unrealized Losses, Less than 12 Months	$ (1,134)	$ (218)
Number of positions, 12 Months or More \| security	10	17
Fair value, 12 Months or More	$ 18,967	$ 30,801
Unrealized Losses, 12 Months or More	$ (1,413)	$ (2,437)
Number of positions \| security	21	19
Fair Value	$ 123,222	$ 53,158
Unrealized Losses	$ (2,547)	$ (2,655)
Held to Maturity:
Number of positions, Less than 12 Months \| security	0	0
Fair Value, Less than 12 Months	$ 0	$ 0
Unrealized Losses, Less than 12 Months	$ 0	$ 0
Number of positions, 12 Months or More \| security	10	10
Fair value, 12 Months or More	$ 47,181	$ 49,603
Unrealized Losses, 12 Months or More	$ (2,604)	$ (4,080)
Number of positions \| security	10	10
Fair Value	$ 47,181	$ 49,603
Unrealized Losses	$ (2,604)	$ (4,080)
Government agency mortgage backed securities \| Residential mortgage backed securities:
Available for Sale:
Number of positions, Less than 12 Months \| security	12	7
Fair Value, Less than 12 Months	$ 153,789	$ 11,051
Unrealized Losses, Less than 12 Months	$ (1,269)	$ (259)
Number of positions, 12 Months or More \| security	34	34
Fair value, 12 Months or More	$ 137,165	$ 141,321
Unrealized Losses, 12 Months or More	$ (18,247)	$ (24,208)
Number of positions \| security	46	41
Fair Value	$ 290,954	$ 152,372
Unrealized Losses	$ (19,516)	$ (24,467)
Held to Maturity:
Number of positions, Less than 12 Months \| security	1	0
Fair Value, Less than 12 Months	$ 15,604	$ 0
Unrealized Losses, Less than 12 Months	$ (637)	$ 0
Number of positions, 12 Months or More \| security	66	69
Fair value, 12 Months or More	$ 318,380	$ 347,154
Unrealized Losses, 12 Months or More	$ (13,739)	$ (25,251)
Number of positions \| security	67	69
Fair Value	$ 333,984	$ 347,154
Unrealized Losses	$ (14,376)	$ (25,251)
Government agency mortgage backed securities \| Commercial mortgage backed securities:
Available for Sale:
Number of positions, Less than 12 Months \| security	8	2
Fair Value, Less than 12 Months	$ 65,008	$ 5,248
Unrealized Losses, Less than 12 Months	$ (687)	$ (122)
Number of positions, 12 Months or More \| security	2	2
Fair value, 12 Months or More	$ 5,542	$ 5,375
Unrealized Losses, 12 Months or More	$ (449)	$ (629)
Number of positions \| security	10	4
Fair Value	$ 70,550	$ 10,623
Unrealized Losses	$ (1,136)	$ (751)
Held to Maturity:
Number of positions, Less than 12 Months \| security	0	0
Fair Value, Less than 12 Months	$ 0	$ 0
Unrealized Losses, Less than 12 Months	$ 0	$ 0
Number of positions, 12 Months or More \| security	1	1
Fair value, 12 Months or More	$ 14,570	$ 14,002
Unrealized Losses, 12 Months or More	$ (2,379)	$ (2,958)
Number of positions \| security	1	1
Fair Value	$ 14,570	$ 14,002
Unrealized Losses	$ (2,379)	$ (2,958)
Government agency collateralized mortgage obligations \| Residential mortgage backed securities:
Available for Sale:
Number of positions, Less than 12 Months \| security	4	3
Fair Value, Less than 12 Months	$ 107,676	$ 48,879
Unrealized Losses, Less than 12 Months	$ (552)	$ (482)
Number of positions, 12 Months or More \| security	37	37
Fair value, 12 Months or More	$ 311,864	$ 311,964
Unrealized Losses, 12 Months or More	$ (65,976)	$ (86,389)
Number of positions \| security	41	40
Fair Value	$ 419,540	$ 360,843
Unrealized Losses	$ (66,528)	$ (86,871)
Held to Maturity:
Number of positions, Less than 12 Months \| security	0	0
Fair Value, Less than 12 Months	$ 0	$ 0
Unrealized Losses, Less than 12 Months	$ 0	$ 0
Number of positions, 12 Months or More \| security	18	18
Fair value, 12 Months or More	$ 311,494	$ 313,376
Unrealized Losses, 12 Months or More	$ (25,999)	$ (41,506)
Number of positions \| security	18	18
Fair Value	$ 311,494	$ 313,376
Unrealized Losses	$ (25,999)	$ (41,506)
Government agency collateralized mortgage obligations \| Commercial mortgage backed securities:
Available for Sale:
Number of positions, Less than 12 Months \| security	6	2
Fair Value, Less than 12 Months	$ 13,658	$ 7,681
Unrealized Losses, Less than 12 Months	$ (26)	$ (39)
Number of positions, 12 Months or More \| security	25	25
Fair value, 12 Months or More	$ 103,541	$ 104,326
Unrealized Losses, 12 Months or More	$ (19,300)	$ (21,556)
Number of positions \| security	31	27
Fair Value	$ 117,199	$ 112,007
Unrealized Losses	$ (19,326)	$ (21,595)
Held to Maturity:
Number of positions, Less than 12 Months \| security	0	0
Fair Value, Less than 12 Months	$ 0	$ 0
Unrealized Losses, Less than 12 Months	$ 0	$ 0
Number of positions, 12 Months or More \| security	9	9
Fair value, 12 Months or More	$ 36,436	$ 36,345
Unrealized Losses, 12 Months or More	$ (6,371)	$ (7,317)
Number of positions \| security	9	9
Fair Value	$ 36,436	$ 36,345
Unrealized Losses	$ (6,371)	$ (7,317)

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