Securities - Gross Unrealized Losses and Fair Value by Investment Category (Details) $ in Thousands	Sep. 30, 2024 USD ($) security	Dec. 31, 2023 USD ($) security
Available for Sale:
Number of positions, Less than 12 Months | security	2	6
Fair Value, Less than 12 Months	$ 3,914	$ 6,819
Unrealized Losses, Less than 12 Months	$ (61)	$ (222)
Number of positions, 12 Months or More | security	123	127
Fair value, 12 Months or More	$ 649,867	$ 685,774
Unrealized Losses, 12 Months or More	$ (114,841)	$ (139,572)
Number of positions | security	125	133
Fair Value	$ 653,781	$ 692,593
Unrealized Losses	$ (114,902)	$ (139,794)
Held to Maturity:
Number of positions, Less than 12 Months | security	1	2
Fair Value, Less than 12 Months	$ 2,370	$ 2,807
Unrealized Losses, Less than 12 Months	$ (10)	$ (25)
Number of positions, 12 Months or More | security	234	234
Fair Value, 12 Months or More	$ 1,047,324	$ 1,117,285
Unrealized Losses, 12 Months or More	$ (81,637)	$ (99,715)
Number of positions | security	235	236
Fair Value	$ 1,049,694	$ 1,120,092
Unrealized Losses	$ (81,647)	$ (99,740)
Obligations of states and political subdivisions
Available for Sale:
Number of positions, Less than 12 Months | security	0	3
Fair Value, Less than 12 Months	$ 0	$ 2,914
Unrealized Losses, Less than 12 Months	$ 0	$ (2)
Number of positions, 12 Months or More | security	7	9
Fair value, 12 Months or More	$ 13,278	$ 15,198
Unrealized Losses, 12 Months or More	$ (1,878)	$ (1,881)
Number of positions | security	7	12
Fair Value	$ 13,278	$ 18,112
Unrealized Losses	$ (1,878)	$ (1,883)
Held to Maturity:
Number of positions, Less than 12 Months | security	1	2
Fair Value, Less than 12 Months	$ 2,370	$ 2,807
Unrealized Losses, Less than 12 Months	$ (10)	$ (25)
Number of positions, 12 Months or More | security	127	126
Fair Value, 12 Months or More	$ 246,559	$ 249,995
Unrealized Losses, 12 Months or More	$ (34,851)	$ (33,663)
Number of positions | security	128	128
Fair Value	$ 248,929	$ 252,802
Unrealized Losses	$ (34,861)	$ (33,688)
Other debt securities
Available for Sale:
Number of positions, Less than 12 Months | security	0	2
Fair Value, Less than 12 Months	$ 0	$ 3,099
Unrealized Losses, Less than 12 Months	$ 0	$ (195)
Number of positions, 12 Months or More | security	18	19
Fair value, 12 Months or More	$ 34,337	$ 35,072
Unrealized Losses, 12 Months or More	$ (2,676)	$ (4,263)
Number of positions | security	18	21
Fair Value	$ 34,337	$ 38,171
Unrealized Losses	$ (2,676)	$ (4,458)
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	$ 51,854	$ 54,254
Unrealized Losses, 12 Months or More	$ (2,578)	$ (4,119)
Number of positions | security	10	10
Fair Value	$ 51,854	$ 54,254
Unrealized Losses	$ (2,578)	$ (4,119)
Government agency mortgage backed securities | Residential mortgage backed securities:
Available for Sale:
Number of positions, Less than 12 Months | security	2	1
Fair Value, Less than 12 Months	$ 3,914	$ 806
Unrealized Losses, Less than 12 Months	$ (61)	$ (25)
Number of positions, 12 Months or More | security	34	35
Fair value, 12 Months or More	$ 152,229	$ 166,963
Unrealized Losses, 12 Months or More	$ (19,116)	$ (24,943)
Number of positions | security	36	36
Fair Value	$ 156,143	$ 167,769
Unrealized Losses	$ (19,177)	$ (24,968)
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	69	70
Fair Value, 12 Months or More	$ 357,350	$ 405,950
Unrealized Losses, 12 Months or More	$ (11,742)	$ (20,314)
Number of positions | security	69	70
Fair Value	$ 357,350	$ 405,950
Unrealized Losses	$ (11,742)	$ (20,314)
Government agency mortgage backed securities | Commercial mortgage backed securities:
Available for Sale:
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	2	2
Fair value, 12 Months or More	$ 5,543	$ 5,392
Unrealized Losses, 12 Months or More	$ (466)	$ (637)
Number of positions | security	2	2
Fair Value	$ 5,543	$ 5,392
Unrealized Losses	$ (466)	$ (637)
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	$ 14,562	$ 14,011
Unrealized Losses, 12 Months or More	$ (2,404)	$ (2,972)
Number of positions | security	1	1
Fair Value	$ 14,562	$ 14,011
Unrealized Losses	$ (2,404)	$ (2,972)
Government agency collateralized mortgage obligations | Residential mortgage backed securities:
Available for Sale:
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	37	37
Fair value, 12 Months or More	$ 336,883	$ 354,574
Unrealized Losses, 12 Months or More	$ (71,481)	$ (85,883)
Number of positions | security	37	37
Fair Value	$ 336,883	$ 354,574
Unrealized Losses	$ (71,481)	$ (85,883)
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	$ 339,359	$ 355,538
Unrealized Losses, 12 Months or More	$ (23,736)	$ (31,670)
Number of positions | security	18	18
Fair Value	$ 339,359	$ 355,538
Unrealized Losses	$ (23,736)	$ (31,670)
Government agency collateralized mortgage obligations | Commercial mortgage backed securities:
Available for Sale:
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	25	25
Fair value, 12 Months or More	$ 107,597	$ 108,575
Unrealized Losses, 12 Months or More	$ (19,224)	$ (21,965)
Number of positions | security	25	25
Fair Value	$ 107,597	$ 108,575
Unrealized Losses	$ (19,224)	$ (21,965)
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	$ 37,640	$ 37,537
Unrealized Losses, 12 Months or More	$ (6,326)	$ (6,977)
Number of positions | security	9	9
Fair Value	$ 37,640	$ 37,537
Unrealized Losses	$ (6,326)	$ (6,977)