Fair Value Measurements and Disclosures - Financial assets measured at fair value on a recurring basis (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Fair Value Measurements and Disclosures
Securities available-for-sale	$ 58,856	$ 50,428
Mortgage loans held-for-investment	10,546	11,422
U.S. asset backed securities
Fair Value Measurements and Disclosures
Securities available-for-sale	11,866
U.S. government agency mortgage-backed securities
Fair Value Measurements and Disclosures
Securities available-for-sale	5,497	23,866
U.S. government agency collateralized mortgage obligations
Fair Value Measurements and Disclosures
Securities available-for-sale	35,223	14,664
State and municipal securities
Fair Value Measurements and Disclosures
Securities available-for-sale	6,270	10,919
Investments in mutual funds
Fair Value Measurements and Disclosures
Securities available-for-sale	1,000	979
Level 3 \| Interest rate lock commitments
Fair Value Measurements and Disclosures
Derivative assets, Fair value	504
Recurring
Fair Value Measurements and Disclosures
Mortgage loans held-for-sale	33,704	37,695
Mortgage loans held-for-investment	10,546	11,422
Mortgage servicing rights	446	213
SBA loan servicing rights	337
Total	105,784	100,209
Recurring \| U.S. asset backed securities
Fair Value Measurements and Disclosures
Securities available-for-sale	11,866
Recurring \| U.S. government agency mortgage-backed securities
Fair Value Measurements and Disclosures
Securities available-for-sale	5,497	23,866
Recurring \| U.S. government agency collateralized mortgage obligations
Fair Value Measurements and Disclosures
Securities available-for-sale	35,223	14,664
Recurring \| State and municipal securities
Fair Value Measurements and Disclosures
Securities available-for-sale	6,270	10,919
Recurring \| Investments in mutual funds
Fair Value Measurements and Disclosures
Securities available-for-sale	1,009	979
Recurring \| Interest rate lock commitments
Fair Value Measurements and Disclosures
Derivative assets, Fair value	504	310
Recurring \| Customer derivatives - Interest rate swaps
Fair Value Measurements and Disclosures
Derivative assets, Fair value	382	141
Recurring \| Level 2
Fair Value Measurements and Disclosures
Mortgage loans held-for-sale	33,704	37,695
Mortgage loans held-for-investment	10,546	11,422
Total	104,497	99,686
Recurring \| Level 2 \| U.S. asset backed securities
Fair Value Measurements and Disclosures
Securities available-for-sale	11,866
Recurring \| Level 2 \| U.S. government agency mortgage-backed securities
Fair Value Measurements and Disclosures
Securities available-for-sale	5,497	23,866
Recurring \| Level 2 \| U.S. government agency collateralized mortgage obligations
Fair Value Measurements and Disclosures
Securities available-for-sale	35,223	14,664
Recurring \| Level 2 \| State and municipal securities
Fair Value Measurements and Disclosures
Securities available-for-sale	6,270	10,919
Recurring \| Level 2 \| Investments in mutual funds
Fair Value Measurements and Disclosures
Securities available-for-sale	1,009	979
Recurring \| Level 2 \| Customer derivatives - Interest rate swaps
Fair Value Measurements and Disclosures
Derivative assets, Fair value	382	141
Recurring \| Level 3
Fair Value Measurements and Disclosures
Mortgage servicing rights	446	213
SBA loan servicing rights	337
Total	1,287	523
Recurring \| Level 3 \| Interest rate lock commitments
Fair Value Measurements and Disclosures
Derivative assets, Fair value	$ 504	$ 310

Fair value portion of mortgage servicing rights.

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Fair value portion of mortgage loans held-for-investment.

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Fair value portion of SBA servicing rights.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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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).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value portion of mortgage loans held-for-sale.

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