Fair Value of Assets and Liabilities - Off-Balance Sheet Credit-Related Commitments (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Carrying amount
Financial Assets
Cash and cash equivalents	$ 61,174	$ 40,651
Loans	1,663,103	1,679,676
Accrued interest receivable	7,412	7,645
Bank-owned life insurance	31,364	30,763
Financial Liabilities
Noninterest-bearing transaction	537,951	550,640
Interest-bearing transaction	1,102,409	1,053,869
Time deposits	192,753	170,587
Deposits held for sale		24,197
Short-term borrowings		93,460
Long-term debt	58,775	58,824
Accrued interest payable	1,879	720
Estimated fair value
Financial Assets
Cash and cash equivalents	61,174	40,651
Loans	1,658,151	1,663,401
Accrued interest receivable	7,412	7,645
Bank-owned life insurance	31,364	30,763
Financial Liabilities
Noninterest-bearing transaction	537,951	550,640
Interest-bearing transaction	1,102,409	1,053,869
Time deposits	192,869	172,616
Deposits held for sale		22,019
Short-term borrowings		93,460
Long-term debt	58,285	59,988
Accrued interest payable	1,879	720
Level 1 | Estimated fair value
Financial Assets
Cash and cash equivalents	61,174	40,651
Accrued interest receivable	7,412	7,645
Financial Liabilities
Short-term borrowings		93,460
Accrued interest payable	1,879	720
Level 2 | Estimated fair value
Financial Assets
Bank-owned life insurance	31,364	30,763
Financial Liabilities
Noninterest-bearing transaction	537,951	550,640
Interest-bearing transaction	1,102,409	1,053,869
Long-term debt	58,285	59,988
Level 3 | Estimated fair value
Financial Assets
Loans	1,658,151	1,663,401
Financial Liabilities
Time deposits	$ 192,869	172,616
Deposits held for sale		$ 22,019