Securities Securities (Available for sale securities in continuous unrealized loss position) (Details) $ in Thousands	Jun. 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	185	173
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 17,144	$ 333,099
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(783)	(35,411)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,354,317	1,062,964
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(159,673)	(132,268)
Debt Securities, Available-for-sale, Unrealized Loss Position	1,371,461	1,396,063
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 160,456	$ 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	135	123
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 10,660	$ 155,944
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(464)	(15,186)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	275,316	154,653
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(44,227)	(30,248)
Debt Securities, Available-for-sale, Unrealized Loss Position	285,976	310,597
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 44,691	$ 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	$ 2,701	$ 38,843
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(41)	(3,031)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	33,085	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(3,075)	0
Debt Securities, Available-for-sale, Unrealized Loss Position	35,786	38,843
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 3,116	$ 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	$ 190	$ 191
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(4)	(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	190	191
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 4	$ 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	1,025	1,034
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(180)	(169)
Debt Securities, Available-for-sale, Unrealized Loss Position	1,025	1,034
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 180	$ 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	$ 3,593	$ 34,511
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(274)	(3,550)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	44,539	17,246
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(7,654)	(4,163)
Debt Securities, Available-for-sale, Unrealized Loss Position	48,132	51,757
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 7,928	$ 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	202,491	141,725
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(28,079)	(21,344)
Debt Securities, Available-for-sale, Unrealized Loss Position	202,491	202,300
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 28,079	$ 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	797,861	748,306
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(76,458)	(76,344)
Debt Securities, Available-for-sale, Unrealized Loss Position	797,861	791,341
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 76,458	$ 82,694

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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