Securities - Gross Unrealized Losses and Fair Value by Investment Category (Details) $ in Thousands	Jun. 30, 2026 USD ($) security	Dec. 31, 2025 USD ($) security
Available for Sale:
Number of positions, Less than 12 Months \| security	160	54
Fair Value, Less than 12 Months	$ 1,337,058	$ 482,669
Unrealized Losses, Less than 12 Months	$ (11,664)	$ (3,204)
Number of positions, 12 Months or More \| security	127	115
Fair value, 12 Months or More	$ 762,383	$ 568,544
Unrealized Losses, 12 Months or More	$ (101,634)	$ (93,355)
Number of positions \| security	287	169
Fair Value	$ 2,099,441	$ 1,051,213
Unrealized Losses	$ (113,298)	$ (96,559)
Held to Maturity:
Number of positions, Less than 12 Months \| security	9	0
Fair Value, Less than 12 Months	$ 47,740	$ 0
Unrealized Losses, Less than 12 Months	$ (1,502)	$ 0
Number of positions, 12 Months or More \| security	218	228
Fair value, 12 Months or More	$ 851,163	$ 959,977
Unrealized Losses, 12 Months or More	$ (78,726)	$ (68,264)
Number of positions \| security	227	228
Fair Value	$ 898,903	$ 959,977
Unrealized Losses	$ (80,228)	$ (68,264)
Obligations of states and political subdivisions
Available for Sale:
Number of positions, Less than 12 Months \| security	46	13
Fair Value, Less than 12 Months	$ 57,548	$ 19,454
Unrealized Losses, Less than 12 Months	$ (1,893)	$ (445)
Number of positions, 12 Months or More \| security	11	7
Fair value, 12 Months or More	$ 15,919	$ 13,591
Unrealized Losses, 12 Months or More	$ (1,847)	$ (1,335)
Number of positions \| security	57	20
Fair Value	$ 73,467	$ 33,045
Unrealized Losses	$ (3,740)	$ (1,780)
Held to Maturity:
Number of positions, Less than 12 Months \| security	5	0
Fair Value, Less than 12 Months	$ 6,301	$ 0
Unrealized Losses, Less than 12 Months	$ (400)	$ 0
Number of positions, 12 Months or More \| security	118	124
Fair value, 12 Months or More	$ 237,908	$ 248,044
Unrealized Losses, 12 Months or More	$ (28,686)	$ (29,516)
Number of positions \| security	123	124
Fair Value	$ 244,209	$ 248,044
Unrealized Losses	$ (29,086)	$ (29,516)
Other debt securities
Available for Sale:
Number of positions, Less than 12 Months \| security	15	10
Fair Value, Less than 12 Months	$ 103,960	$ 191,504
Unrealized Losses, Less than 12 Months	$ (426)	$ (1,347)
Number of positions, 12 Months or More \| security	11	8
Fair value, 12 Months or More	$ 183,380	$ 14,571
Unrealized Losses, 12 Months or More	$ (1,586)	$ (967)
Number of positions \| security	26	18
Fair Value	$ 287,340	$ 206,075
Unrealized Losses	$ (2,012)	$ (2,314)
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	$ 39,353	$ 45,351
Unrealized Losses, 12 Months or More	$ (2,523)	$ (2,062)
Number of positions \| security	10	10
Fair Value	$ 39,353	$ 45,351
Unrealized Losses	$ (2,523)	$ (2,062)
Agency mortgage-backed securities \| Residential mortgage-backed securities:
Available for Sale:
Number of positions, Less than 12 Months \| security	39	8
Fair Value, Less than 12 Months	$ 698,540	$ 135,320
Unrealized Losses, Less than 12 Months	$ (5,333)	$ (903)
Number of positions, 12 Months or More \| security	38	36
Fair value, 12 Months or More	$ 179,487	$ 132,975
Unrealized Losses, 12 Months or More	$ (16,759)	$ (14,772)
Number of positions \| security	77	44
Fair Value	$ 878,027	$ 268,295
Unrealized Losses	$ (22,092)	$ (15,675)
Held to Maturity:
Number of positions, Less than 12 Months \| security	4	0
Fair Value, Less than 12 Months	$ 41,439	$ 0
Unrealized Losses, Less than 12 Months	$ (1,102)	$ 0
Number of positions, 12 Months or More \| security	62	66
Fair value, 12 Months or More	$ 244,036	$ 313,963
Unrealized Losses, 12 Months or More	$ (13,970)	$ (10,030)
Number of positions \| security	66	66
Fair Value	$ 285,475	$ 313,963
Unrealized Losses	$ (15,072)	$ (10,030)
Agency mortgage-backed securities \| Commercial mortgage-backed securities:
Available for Sale:
Number of positions, Less than 12 Months \| security	15	9
Fair Value, Less than 12 Months	$ 71,420	$ 71,188
Unrealized Losses, Less than 12 Months	$ (516)	$ (395)
Number of positions, 12 Months or More \| security	1	2
Fair value, 12 Months or More	$ 4,636	$ 5,595
Unrealized Losses, 12 Months or More	$ (302)	$ (367)
Number of positions \| security	16	11
Fair Value	$ 76,056	$ 76,783
Unrealized Losses	$ (818)	$ (762)
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	$ 14,700	$ 14,879
Unrealized Losses, 12 Months or More	$ (2,113)	$ (2,059)
Number of positions \| security	1	1
Fair Value	$ 14,700	$ 14,879
Unrealized Losses	$ (2,113)	$ (2,059)
Collateralized mortgage obligations \| Residential mortgage-backed securities:
Available for Sale:
Number of positions, Less than 12 Months \| security	10	2
Fair Value, Less than 12 Months	$ 236,409	$ 24,816
Unrealized Losses, Less than 12 Months	$ (1,553)	$ (58)
Number of positions, 12 Months or More \| security	38	37
Fair value, 12 Months or More	$ 277,694	$ 299,606
Unrealized Losses, 12 Months or More	$ (62,762)	$ (57,850)
Number of positions \| security	48	39
Fair Value	$ 514,103	$ 324,422
Unrealized Losses	$ (64,315)	$ (57,908)
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	$ 279,785	$ 301,657
Unrealized Losses, 12 Months or More	$ (25,284)	$ (18,600)
Number of positions \| security	18	18
Fair Value	$ 279,785	$ 301,657
Unrealized Losses	$ (25,284)	$ (18,600)
Collateralized mortgage obligations \| Commercial mortgage-backed securities:
Available for Sale:
Number of positions, Less than 12 Months \| security	35	12
Fair Value, Less than 12 Months	$ 169,181	$ 40,387
Unrealized Losses, Less than 12 Months	$ (1,943)	$ (56)
Number of positions, 12 Months or More \| security	28	25
Fair value, 12 Months or More	$ 101,267	$ 102,206
Unrealized Losses, 12 Months or More	$ (18,378)	$ (18,064)
Number of positions \| security	63	37
Fair Value	$ 270,448	$ 142,593
Unrealized Losses	$ (20,321)	$ (18,120)
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	$ 35,381	$ 36,083
Unrealized Losses, 12 Months or More	$ (6,150)	$ (5,997)
Number of positions \| security	9	9
Fair Value	$ 35,381	$ 36,083
Unrealized Losses	$ (6,150)	$ (5,997)

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