Loans (Narrative) (Details) $ in Thousands		Mar. 31, 2021 USD ($) loan security	Dec. 31, 2020 USD ($)
Carrying value of PPP loans		$ 228,600	$ 199,800
Loans Receivable Net Deferred Cost Originated		(223)	1,500
Loans Receivable Net Deferred Premium on Purchased Loans		653	787
Accrued interest receivable on loans		11,800	11,300
Loans pledged as collateral		$ 2,100,000	2,100,000
Number of executed loan modifications due to COVID-19 | security		652
Balance of executed loan modifications due to COVID-19		$ 727,000
Number of active deferrals due to COVID-19 | loan		88
Balance of active deferments due to COVID-19		$ 191,400
Past due loans included in nonaccrual loans		8,400	8,500
Nonaccrual loans with no ACL		4,300	3,000
Residential loans in process of foreclosure		3,100	3,400
Nonaccrual loans current on payment		4,600	4,700
Individually analyzed loans		16,800	18,300
Collateral dependent loans	[1]	$ 4,194,666	4,195,990
Active deferments as % of total loans excl PPP loans		5.00%
Collateral Dependent Individually Analyzed
Collateral dependent loans		$ 6,942	$ 8,444

[1] Includes net unamortized loan origination fees of $223 thousand at March 31, 2021 and net unamortized loan origination costs of $1.5 million, at December 31, 2020 and net unamortized premiums on purchased loans of $653 thousand and $787 thousand, respectively, at March 31, 2021 and December 31, 2020.