Fair Value Measurements and Disclosures - Estimated fair values of financial instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Financial assets:
Securities available-for-sale	$ 90,552	$ 58,856
Securities held-to-maturity	7,946	9,003
Equity Investments	1,025	1,009
Mortgage loans held-for-investment	10,553	10,546
Carrying amount
Financial assets:
Restricted investment in bank stock	8,347	8,072
Level 1 | Carrying amount
Financial assets:
Cash and cash equivalents	37,522	39,371
Level 1 | Fair value
Financial assets:
Cash and cash equivalents	37,522	39,371
Level 2 | Carrying amount
Financial assets:
Securities available-for-sale	90,552	58,856
Securities held-to-maturity	7,747	8,780
Equity Investments	1,025	1,009
Mortgage loans held-for-sale	107,506	33,704
Mortgage loans held-for-investment	10,553	10,546
Financial liabilities:
Deposits	993,753	851,168
Short-term borrowings	129,707	123,676
Long-term debt	5,023	3,123
Subordinated debentures	40,885	40,962
Accrued interest payable	1,578	1,088
Level 2 | Carrying amount | Forward Commitments
Financial assets:
Derivative asset		6
Financial liabilities:
Derivatives	2,424	119
Level 2 | Carrying amount | Customer derivatives - Interest rate swaps
Financial assets:
Derivative asset	1,057	382
Financial liabilities:
Derivatives	1,183	431
Level 2 | Fair value
Financial assets:
Securities available-for-sale	90,552	58,856
Securities held-to-maturity	7,946	9,003
Equity Investments	1,025	1,009
Mortgage loans held-for-sale	107,506	33,704
Mortgage loans held-for-investment	10,553	10,546
Financial liabilities:
Deposits	1,116,400	880,400
Short-term borrowings	129,707	123,678
Long-term debt	5,100	3,123
Subordinated debentures	39,080	40,962
Accrued interest payable	1,578	1,088
Level 2 | Fair value | Forward Commitments
Financial assets:
Derivative asset		6
Financial liabilities:
Derivatives	2,424	119
Level 2 | Fair value | Customer derivatives - Interest rate swaps
Financial assets:
Derivative asset	1,057	382
Financial liabilities:
Derivatives	1,183	431
Level 3 | Interest rate lock commitments
Financial assets:
Derivative asset	4,021	504
Level 3 | Carrying amount
Financial assets:
Loans receivable, net of the allowance and lease losses	999,910	944,651
Accrued interest receivable	3,283	3,148
Level 3 | Carrying amount | Interest rate lock commitments
Financial assets:
Derivative asset	4,021	504
Financial liabilities:
Derivatives	332	157
Level 3 | Fair value
Financial assets:
Loans receivable, net of the allowance and lease losses	1,035,010	973,057
Accrued interest receivable	3,283	3,148
Level 3 | Fair value | Interest rate lock commitments
Financial assets:
Derivative asset	4,021	504
Financial liabilities:
Derivatives	$ 332	$ 157