Securities - Fair Value and Age of Gross Unrealized Losses of Debt Securities (Details) $ in Thousands	Mar. 31, 2023 USD ($) security	Dec. 31, 2022 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Number of Securities, Less Than 12 Months | security	33	116
Fair Value, Less Than 12 Months	$ 232,123	$ 663,656
Unrealized Losses, Less Than 12 Months	$ (6,273)	$ (46,120)
Number of Securities, 12 Months or More | security	94	31
Fair Value, 12 Months or More	$ 694,891	$ 308,067
Unrealized Losses, 12 Months or More	$ (82,675)	$ (56,462)
Number of Securities, Total | security	127	147
Fair Value, Total	$ 927,014	$ 971,723
Unrealized Losses, Total	$ (88,948)	$ (102,582)
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Number of Securities, Less Than 12 Months | security	1	6
Fair Value, Less Than 12 Months	$ 9,413	$ 57,057
Unrealized Losses, Less Than 12 Months	$ (112)	$ (3,363)
Number of Securities, 12 Months or More | security	12	8
Fair Value, 12 Months or More	$ 114,151	$ 74,638
Unrealized Losses, 12 Months or More	$ (11,342)	$ (10,358)
Number of Securities, Total | security	13	14
Fair Value, Total	$ 123,564	$ 131,695
Unrealized Losses, Total	$ (11,454)	$ (13,721)
Obligations of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Number of Securities, Less Than 12 Months | security	4	6
Fair Value, Less Than 12 Months	$ 27,382	$ 41,811
Unrealized Losses, Less Than 12 Months	$ (618)	$ (1,668)
Number of Securities, 12 Months or More | security	2	0
Fair Value, 12 Months or More	$ 14,713	$ 0
Unrealized Losses, 12 Months or More	$ (732)	$ 0
Number of Securities, Total | security	6	6
Fair Value, Total	$ 42,095	$ 41,811
Unrealized Losses, Total	$ (1,350)	$ (1,668)
Collateralized mortgage obligations of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Number of Securities, Less Than 12 Months | security	16	47
Fair Value, Less Than 12 Months	$ 130,667	$ 296,509
Unrealized Losses, Less Than 12 Months	$ (3,867)	$ (28,153)
Number of Securities, 12 Months or More | security	43	13
Fair Value, 12 Months or More	$ 283,266	$ 112,902
Unrealized Losses, 12 Months or More	$ (43,507)	$ (25,682)
Number of Securities, Total | security	59	60
Fair Value, Total	$ 413,933	$ 409,411
Unrealized Losses, Total	$ (47,374)	$ (53,835)
Residential mortgage-backed securities of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Number of Securities, Less Than 12 Months | security	3	25
Fair Value, Less Than 12 Months	$ 1,487	$ 7,143
Unrealized Losses, Less Than 12 Months	$ (69)	$ (589)
Number of Securities, 12 Months or More | security	12	3
Fair Value, 12 Months or More	$ 39,280	$ 34,223
Unrealized Losses, 12 Months or More	$ (7,039)	$ (7,245)
Number of Securities, Total | security	15	28
Fair Value, Total	$ 40,767	$ 41,366
Unrealized Losses, Total	$ (7,108)	$ (7,834)
Commercial mortgage-backed securities of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Number of Securities, Less Than 12 Months | security	9	30
Fair Value, Less Than 12 Months	$ 63,174	$ 241,009
Unrealized Losses, Less Than 12 Months	$ (1,607)	$ (11,975)
Number of Securities, 12 Months or More | security	25	7
Fair Value, 12 Months or More	$ 243,481	$ 86,304
Unrealized Losses, 12 Months or More	$ (20,055)	$ (13,177)
Number of Securities, Total | security	34	37
Fair Value, Total	$ 306,655	$ 327,313
Unrealized Losses, Total	$ (21,662)	$ (25,152)
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Number of Securities, Less Than 12 Months | security	0	2
Fair Value, Less Than 12 Months	$ 0	$ 20,127
Unrealized Losses, Less Than 12 Months	$ 0	$ (372)
Number of Securities, 12 Months or More | security	0	0
Fair Value, 12 Months or More	$ 0	$ 0
Unrealized Losses, 12 Months or More	$ 0	$ 0
Number of Securities, Total | security	0	2
Fair Value, Total	$ 0	$ 20,127
Unrealized Losses, Total	$ 0	$ (372)