Fair Value Measurements and Disclosures - Financial assets measured at fair value on a recurring basis (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Assets
Securities available-for-sale	$ 123,562	$ 58,856
Equity investments	1,031	1,009
Mortgage loans held-for-investment	12,182	10,546
U.S. asset backed securities
Assets
Securities available-for-sale	25,592	11,866
U.S. government agency mortgage-backed securities
Assets
Securities available-for-sale	4,046	5,497
U.S. government agency collateralized mortgage obligations
Assets
Securities available-for-sale	23,909	35,223
State and municipal securities
Assets
Securities available-for-sale	65,810	6,270
Corporate bonds
Assets
Securities available-for-sale	4,205
Level 3 \| Interest rate lock commitments
Assets
Derivative assets, Fair value	6,932	504
Recurring
Assets
Securities available-for-sale	1,031
Mortgage loans held-for-sale	229,199	33,704
Mortgage loans held-for-investment	12,182	10,546
Total	374,024	105,007
Liabilities
Total	2,891	707
Recurring \| U.S. asset backed securities
Assets
Securities available-for-sale	25,592	11,866
Recurring \| U.S. government agency mortgage-backed securities
Assets
Securities available-for-sale	4,046	5,497
Recurring \| U.S. government agency collateralized mortgage obligations
Assets
Securities available-for-sale	23,909	35,223
Recurring \| State and municipal securities
Assets
Securities available-for-sale	65,810	6,270
Recurring \| Corporate bonds
Assets
Securities available-for-sale	4,205
Recurring \| Investments in mutual funds
Assets
Securities available-for-sale		1,009
Recurring \| Interest rate lock commitments
Assets
Derivative assets, Fair value	6,932	504
Liabilities
Derivative Liability	100	157
Recurring \| Forward Commitments
Assets
Securities available-for-sale		6
Liabilities
Derivative Liability	1,572	119
Recurring \| Customer derivatives - interest rate swaps
Assets
Derivative assets, Fair value	1,118	382
Liabilities
Derivative Liability	1,219	431
Recurring \| Level 2
Assets
Securities available-for-sale	1,031
Mortgage loans held-for-sale	229,199	33,704
Mortgage loans held-for-investment	12,182	10,546
Total	367,092	104,503
Liabilities
Total	2,791	550
Recurring \| Level 2 \| U.S. asset backed securities
Assets
Securities available-for-sale	25,592	11,866
Recurring \| Level 2 \| U.S. government agency mortgage-backed securities
Assets
Securities available-for-sale	4,046	5,497
Recurring \| Level 2 \| U.S. government agency collateralized mortgage obligations
Assets
Securities available-for-sale	23,909	35,223
Recurring \| Level 2 \| State and municipal securities
Assets
Securities available-for-sale	65,810	6,270
Recurring \| Level 2 \| Corporate bonds
Assets
Securities available-for-sale	4,205
Recurring \| Level 2 \| Investments in mutual funds
Assets
Securities available-for-sale		1,009
Recurring \| Level 2 \| Forward Commitments
Assets
Securities available-for-sale		6
Liabilities
Derivative Liability	1,572	119
Recurring \| Level 2 \| Customer derivatives - interest rate swaps
Assets
Derivative assets, Fair value	1,118	382
Liabilities
Derivative Liability	1,219	431
Recurring \| Level 3
Assets
Total	6,932	504
Liabilities
Total	100	157
Recurring \| Level 3 \| Interest rate lock commitments
Assets
Derivative assets, Fair value	6,932	504
Liabilities
Derivative Liability	$ 100	$ 157

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

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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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