Securities Securities (Available for sale securities in continuous unrealized loss position) (Details) $ in Thousands	Sep. 30, 2023 USD ($) holding	Dec. 31, 2022 USD ($) holding
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions \| holding	183	173
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 5,896	$ 333,099
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(112)	(35,411)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,347,368	1,062,964
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(170,701)	(132,268)
Debt Securities, Available-for-sale, Unrealized Loss Position	1,353,264	1,396,063
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 170,813	$ 167,679
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	133	123
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 3,182	$ 155,944
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(67)	(15,186)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	271,047	154,653
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(51,545)	(30,248)
Debt Securities, Available-for-sale, Unrealized Loss Position	274,229	310,597
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 51,612	$ 45,434
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	13	13
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 2,530	$ 38,843
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(35)	(3,031)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	31,119	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(3,475)	0
Debt Securities, Available-for-sale, Unrealized Loss Position	33,649	38,843
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 3,510	$ 3,031
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	$ 184	$ 191
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(10)	(2)
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	184	191
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 10	$ 2
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	1,043	1,034
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(161)	(169)
Debt Securities, Available-for-sale, Unrealized Loss Position	1,043	1,034
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 161	$ 169
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	$ 34,511
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	(3,550)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	45,763	17,246
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(9,067)	(4,163)
Debt Securities, Available-for-sale, Unrealized Loss Position	45,763	51,757
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 9,067	$ 7,713
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	$ 60,575
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	(7,292)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	199,509	141,725
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(30,877)	(21,344)
Debt Securities, Available-for-sale, Unrealized Loss Position	199,509	202,300
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 30,877	$ 28,636
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	18	18
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 0	$ 43,035
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	(6,350)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	798,887	748,306
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(75,576)	(76,344)
Debt Securities, Available-for-sale, Unrealized Loss Position	798,887	791,341
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 75,576	$ 82,694

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