Fair Value Measurements and Disclosures - Financial assets measured at fair value on a recurring basis (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Assets
Securities available-for-sale	$ 134,165	$ 123,562
Equity investments	1,013	1,031
Mortgage loans held-for-investment	13,590	12,182
U.S. asset backed securities
Assets
Securities available-for-sale	27,230	25,592
U.S. government agency mortgage-backed securities
Assets
Securities available-for-sale	3,922	4,046
U.S. government agency collateralized mortgage obligations
Assets
Securities available-for-sale	23,519	23,909
State and municipal securities
Assets
Securities available-for-sale	72,648	65,810
Corporate bonds
Assets
Securities available-for-sale	4,930	4,205
Level 3 \| Interest rate lock commitments
Assets
Derivative assets, Fair value	3,285	6,932
Recurring
Assets
Equity investments	1,013	1,031
Mortgage loans held-for-sale	170,248	229,199
Mortgage loans held-for-investment	13,590	12,182
Total	324,284	374,024
Liabilities
Total	1,053	2,891
Recurring \| U.S. asset backed securities
Assets
Securities available-for-sale	27,230	25,592
Recurring \| U.S. government agency mortgage-backed securities
Assets
Securities available-for-sale	3,922	4,046
Recurring \| U.S. government agency collateralized mortgage obligations
Assets
Securities available-for-sale	23,519	23,909
Recurring \| State and municipal securities
Assets
Securities available-for-sale	72,648	65,810
Recurring \| U.S. Treasuries
Assets
Securities available-for-sale	1,916
Recurring \| Corporate bonds
Assets
Securities available-for-sale	4,930	4,205
Recurring \| Interest rate lock commitments
Assets
Derivative assets, Fair value	3,285	6,932
Liabilities
Derivative Liability	890	100
Recurring \| Forward Commitments
Assets
Derivative assets, Fair value	1,832
Liabilities
Derivative Liability	8	1,572
Recurring \| Customer derivatives - interest rate swaps
Assets
Derivative assets, Fair value	151	1,118
Liabilities
Derivative Liability	155	1,219
Recurring \| Level 2
Assets
Equity investments	1,013	1,031
Mortgage loans held-for-sale	170,248	229,199
Mortgage loans held-for-investment	13,590	12,182
Total	320,999	367,092
Liabilities
Total	163	2,791
Recurring \| Level 2 \| U.S. asset backed securities
Assets
Securities available-for-sale	27,230	25,592
Recurring \| Level 2 \| U.S. government agency mortgage-backed securities
Assets
Securities available-for-sale	3,922	4,046
Recurring \| Level 2 \| U.S. government agency collateralized mortgage obligations
Assets
Securities available-for-sale	23,519	23,909
Recurring \| Level 2 \| State and municipal securities
Assets
Securities available-for-sale	72,648	65,810
Recurring \| Level 2 \| U.S. Treasuries
Assets
Securities available-for-sale	1,916
Recurring \| Level 2 \| Corporate bonds
Assets
Securities available-for-sale	4,930	4,205
Recurring \| Level 2 \| Forward Commitments
Assets
Derivative assets, Fair value	1,832
Liabilities
Derivative Liability	8	1,572
Recurring \| Level 2 \| Customer derivatives - interest rate swaps
Assets
Derivative assets, Fair value	151	1,118
Liabilities
Derivative Liability	155	1,219
Recurring \| Level 3
Assets
Total	3,285	6,932
Liabilities
Total	890	100
Recurring \| Level 3 \| Interest rate lock commitments
Assets
Derivative assets, Fair value	3,285	6,932
Liabilities
Derivative Liability	$ 890	$ 100

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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Fair value, after the effects of master netting arrangements, of a financial liability or 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 liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value of financial and nonfinancial obligations.

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