Securities (Reconciliation of fair value of available for sale securities) (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Reconciliation of fair value of securities
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	$ 2,146,923	$ 2,051,822
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1,360	8,302
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(72,311)	(55,877)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Debt Securities, Available-for-Sale, Excluding Accrued Interest	2,075,972	2,004,247
U.S. government agency securities
Reconciliation of fair value of securities
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	228,317	228,697
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(9,529)	(10,025)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Debt Securities, Available-for-Sale, Excluding Accrued Interest	218,788	218,672
U.S. treasury securities
Reconciliation of fair value of securities
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	390,700	485,388
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	32
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(11,525)	(14,336)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Debt Securities, Available-for-Sale, Excluding Accrued Interest	379,175	471,084
Agency mortgage-backed securities
Reconciliation of fair value of securities
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	996,262	790,764
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	746	4,430
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(35,199)	(22,231)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Debt Securities, Available-for-Sale, Excluding Accrued Interest	961,809	772,963
Agency Collateralized Mortgage Obligations [Member]
Reconciliation of fair value of securities
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	261,338	273,321
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	126	784
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(9,935)	(4,529)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Debt Securities, Available-for-Sale, Excluding Accrued Interest	251,529	269,576
US States and Political Subdivisions Debt Securities [Member]
Reconciliation of fair value of securities
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	229,525	230,052
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	488	3,056
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(1,212)	(30)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Debt Securities, Available-for-Sale, Excluding Accrued Interest	228,801	233,078
Pooled trust preferred securities issued by banks and insurers
Reconciliation of fair value of securities
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	1,035	1,120
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(69)	(78)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Debt Securities, Available-for-Sale, Excluding Accrued Interest	966	1,042
Small Business Administration Pooled Securities [Member]
Reconciliation of fair value of securities
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	39,746	42,480
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(4,842)	(4,648)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Debt Securities, Available-for-Sale, Excluding Accrued Interest	$ 34,904	$ 37,832

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

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- Definition

Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

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Amount excluding accrued interest, of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

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Amortized cost excluding accrued interest, before allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

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