Short-Term Borrowings - Federal Funds Purchased and Short-term Borrowings (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Securities Sold Under Agreements to Repurchase:
Balance at Period End, Amount	$ 42,061	$ 30,571
Securities Sold under Agreements to Repurchase
Securities Sold Under Agreements to Repurchase:
Balance at Period End, Amount	$ 42,061	$ 30,571
Balance at Period End, Weighted Average Rate	0.21%	0.57%
Average Balance Outstanding During the Period, Amount	$ 35,922	$ 29,976
Average Balance Outstanding During the Period, Weighted Average Interest Rate	0.42%	0.62%
Maximum Amount Outstanding at any Month End, Amount	$ 43,367	$ 34,197
Securities Collaterizing the Agreements at Period-End:
Carrying Value, Amount	44,601	37,584
Market Value, Amount	$ 45,767	$ 37,873