Loans (Narrative) (Details) $ in Thousands		12 Months Ended
		Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Net unamortized loan origination costs		$ 13,000	$ 11,600
Net unamortized premiums on purchased loans		286	318
Accrued interest receivable		22,900	17,600
Total loans	[1]	5,647,706	5,110,139
Nonaccrual loans included in past due loans		6,900	7,200
Nonaccrual loans current on payment		37,700	5,700
Residential loans in process of foreclosure		960	2,900
Individually analyzed loans		$ 34,600	$ 10,000
Number of loans modified			3
Payment Default [Member]
Number of loans modified		0	0
Asset Pledged as Collateral
Total loans		$ 3,400,000	$ 2,400,000
Collateral Dependent Individually Analyzed [Member]
Total loans		$ 34,640	$ 8,455

[1] Includes net unamortized loan origination costs of $13.0 million and $11.6 million, respectively, at December 31, 2023 and 2022 and net unamortized premiums on loans purchased from and serviced by other financial institutions of $286 thousand and $318 thousand, respectively, at December 31, 2023 and 2022.