Securities Securities (Available for sale securities in continuous unrealized loss position) (Details) $ in Thousands	Mar. 31, 2024 USD ($) holding	Dec. 31, 2023 USD ($) holding
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions \| holding	172	163
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 2,123	$ 1,620
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(23)	(18)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,268,945	1,328,959
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(129,560)	(125,618)
Debt Securities, Available-for-sale, Unrealized Loss Position	1,271,068	1,330,579
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 129,583	$ 125,636
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions \| holding	125	115
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 857	$ 1,091
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(8)	(11)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	267,985	273,447
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(38,972)	(37,235)
Debt Securities, Available-for-sale, Unrealized Loss Position	268,842	274,538
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 38,980	$ 37,246
Collateralized Debt Obligations [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions \| holding	12	12
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 1,075	$ 339
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(11)	(2)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	31,013	31,682
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(2,545)	(2,528)
Debt Securities, Available-for-sale, Unrealized Loss Position	32,088	32,021
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 2,556	$ 2,530
US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions \| holding	1	1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 191	$ 190
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(4)	(5)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Unrealized Loss Position	191	190
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 4	$ 5
Pooled trust preferred securities issued by banks and insurers
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions \| holding	1	1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 0	$ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,036	1,018
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(144)	(170)
Debt Securities, Available-for-sale, Unrealized Loss Position	1,036	1,018
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 144	$ 170
Small Business Administration Pooled Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions \| holding	8	8
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 0	$ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	44,397	46,572
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(7,686)	(7,130)
Debt Securities, Available-for-sale, Unrealized Loss Position	44,397	46,572
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 7,686	$ 7,130
U.S. government agency securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions \| holding	9	9
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 0	$ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	205,676	207,138
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(24,337)	(23,060)
Debt Securities, Available-for-sale, Unrealized Loss Position	205,676	207,138
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 24,337	$ 23,060
US Treasury Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions \| holding	16	17
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 0	$ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	718,838	769,102
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(55,876)	(55,495)
Debt Securities, Available-for-sale, Unrealized Loss Position	718,838	769,102
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 55,876	$ 55,495

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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