Short-Term Borrowings and Long-Term Debt (Schedule of Debt) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Long-term debt
Long-term debt outstanding at end of period	$ 27,302	$ 40,370
Weighted average rate on outstanding long-term debt	0.61%	2.31%
Maximum outstanding long-term debt of any month end	$ 67,359	$ 55,392
Average outstanding long-term debt	$ 53,615	$ 32,702
Approximate average rate paid on long-term debt	2.56%	2.27%
Short-term borrowings
Short-term borrowings outstanding at end of period	$ 0	$ 5,000
Weighted average rate on short-term borrowings	0.00%	1.81%
Maximum outstanding short-term borrowings at any month end	$ 27,000	$ 59,500
Average outstanding short-term borrowings	$ 8,156	$ 30,965
Approximate average rate paid on short-term borrowings	1.36%	2.50%
PPPLF advances
PPPLF advances outstanding at end of period	$ 0
Weighted average rate on PPPLF advances	0.00%
Maximum outstanding PPPLF advances at any month end	$ 127,674
Average outstanding PPPLF advances	$ 60,360
Approximate average rate paid on PPPLF advances	0.35%