Fair Value of Financial Instruments and Fair Value Measurements - Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Assets
Investment securities available for sale, at fair value	$ 433,729	$ 380,814
Carrying Value
Assets
Cash and short-term investments	181,588	183,506
Investment securities available for sale, at fair value	433,729	380,814
Other investments, at cost	2,703	3,296
Loans held for sale	28,429	52,386
Loans, net	1,050,082	1,047,376
Liabilities
Deposits	1,525,884	1,445,027
Federal Home Loan Bank advances	22,500	22,500
Carrying Value \| Paycheck Protection Program Liquidity Facility
Liabilities
Long-term debt	60,602	106,789
Carrying Value \| Other borrowings
Liabilities
Long-term debt	37,542	37,792
Estimated Fair Value
Assets
Cash and short-term investments	181,588	183,506
Investment securities available for sale, at fair value	433,729	380,814
Other investments, at cost	2,703	3,296
Loans held for sale	28,429	52,386
Loans, net	1,061,554	1,063,785
Liabilities
Deposits	1,526,740	1,445,984
Federal Home Loan Bank advances	21,312	20,817
Estimated Fair Value \| Paycheck Protection Program Liquidity Facility
Liabilities
Long-term debt	60,602	106,789
Estimated Fair Value \| Other borrowings
Liabilities
Long-term debt	37,767	37,792
Estimated Fair Value \| Level 1
Assets
Cash and short-term investments	181,588	183,506
Investment securities available for sale, at fair value	0	245
Other investments, at cost	0	0
Loans held for sale	0	0
Loans, net	0	0
Liabilities
Deposits	0	0
Federal Home Loan Bank advances	0	0
Estimated Fair Value \| Level 1 \| Paycheck Protection Program Liquidity Facility
Liabilities
Long-term debt	0	0
Estimated Fair Value \| Level 1 \| Other borrowings
Liabilities
Long-term debt	0	0
Estimated Fair Value \| Level 2
Assets
Cash and short-term investments	0	0
Investment securities available for sale, at fair value	433,729	380,569
Other investments, at cost	2,703	3,296
Loans held for sale	28,429	52,386
Loans, net	0	0
Liabilities
Deposits	1,526,740	1,445,984
Federal Home Loan Bank advances	21,312	20,817
Estimated Fair Value \| Level 2 \| Paycheck Protection Program Liquidity Facility
Liabilities
Long-term debt	60,602	106,789
Estimated Fair Value \| Level 2 \| Other borrowings
Liabilities
Long-term debt	37,767	37,792
Estimated Fair Value \| Level 3
Assets
Cash and short-term investments	0	0
Investment securities available for sale, at fair value	0	0
Other investments, at cost	0	0
Loans held for sale	0	0
Loans, net	1,061,554	1,063,785
Liabilities
Deposits	0	0
Federal Home Loan Bank advances	0	0
Estimated Fair Value \| Level 3 \| Paycheck Protection Program Liquidity Facility
Liabilities
Long-term debt	0
Estimated Fair Value \| Level 3 \| Other borrowings
Liabilities
Long-term debt	$ 0	$ 0

Other Investments, Fair Value Disclosure

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Fair value of Federal Home Loan Bank (FHLBank) advances carried under the fair value option.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
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- Definition

Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

+ References

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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