Fair Values of Financial Instruments - Estimated Fair Value and Related Carrying Values of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Carrying Amount
Financial assets:
Cash and due from banks	$ 36,295	$ 24,347
Interest bearing deposits	27,586	4,093
Federal funds sold	31,230	1,254
Securities: Available for sale	106,256	51,300
Loans, net of allowance for credit losses	990,239	625,513
Accrued interest receivable	3,138	2,103
Federal Home Loan Bank stock	5,180	2,652
Atlantic Central Bankers stock	131	131
Other investments	2,838	1,537
Financial liabilities:
Deposits	1,006,781	614,926
Accrued interest payable	572	392
FHLB advances, notes payable, and financing leases	106,270	56,989
Unrecognized financial instruments:
Commitments to extend credit	184,376	114,395
Standby letters of credit	4,045	3,276
Estimated Fair Value
Financial assets:
Cash and due from banks	36,295	24,347
Interest bearing deposits	27,586	4,093
Federal funds sold	31,230	1,254
Securities: Available for sale	106,256	51,300
Loans, net of allowance for credit losses	976,636	604,290
Accrued interest receivable	3,138	2,103
Federal Home Loan Bank stock	5,180	2,652
Atlantic Central Bankers stock	131	131
Other investments	2,838	1,537
Financial liabilities:
Deposits	1,008,842	570,509
Accrued interest payable	572	392
FHLB advances, notes payable, and financing leases	109,260	56,979
Unrecognized financial instruments:
Commitments to extend credit	184,376	114,395
Standby letters of credit	$ 4,045	$ 3,276