Securities Securities (Available for sale securities in continuous unrealized loss position) (Details) $ in Thousands	Sep. 30, 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	145	163
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 47,479	$ 1,620
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(188)	(18)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,194,020	1,328,959
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(87,402)	(125,618)
Debt Securities, Available-for-sale, Unrealized Loss Position	1,241,499	1,330,579
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 87,590	$ 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	104	115
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 47,479	$ 1,091
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(188)	(11)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	266,901	273,447
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(29,094)	(37,235)
Debt Securities, Available-for-sale, Unrealized Loss Position	314,380	274,538
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 29,282	$ 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	9	12
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 0	$ 339
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		(2)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	28,452	31,682
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1,646)	(2,528)
Debt Securities, Available-for-sale, Unrealized Loss Position	28,452	32,021
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 1,646	$ 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
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months		$ 190
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		(5)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer		0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		0
Debt Securities, Available-for-sale, Unrealized Loss Position		190
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss		$ 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	1,027	1,018
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(153)	(170)
Debt Securities, Available-for-sale, Unrealized Loss Position	1,027	1,018
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 153	$ 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	43,643	46,572
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(5,944)	(7,130)
Debt Securities, Available-for-sale, Unrealized Loss Position	43,643	46,572
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 5,944	$ 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	213,084	207,138
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(16,558)	(23,060)
Debt Securities, Available-for-sale, Unrealized Loss Position	213,084	207,138
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 16,558	$ 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	14	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	640,913	769,102
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(34,007)	(55,495)
Debt Securities, Available-for-sale, Unrealized Loss Position	640,913	769,102
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 34,007	$ 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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