Fair Value Measurements and Disclosures - Financial assets measured at fair value on a recurring basis (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Assets
Securities available-for-sale	$ 146,149	$ 123,562
Equity investments	1,011	1,031
Mortgage loans held-for-investment	17,142	12,182
U.S. asset backed securities
Assets
Securities available-for-sale	21,293	25,592
U.S. government agency mortgage-backed securities
Assets
Securities available-for-sale	5,459	4,046
U.S. government agency collateralized mortgage obligations
Assets
Securities available-for-sale	24,053	23,909
State and municipal securities
Assets
Securities available-for-sale	72,828	65,810
Non-U.S. government agencies collateralized mortgage obligations
Assets
Securities available-for-sale	999
Corporate bonds
Assets
Securities available-for-sale	6,507	4,205
Level 3 \| Interest rate lock commitments
Assets
Derivative assets, Fair value	1,712	6,932
Recurring
Assets
Equity investments	1,011	1,031
Mortgage loans held-for-sale	117,996	229,199
Mortgage loans held-for-investment	17,142	12,182
Total	285,509	374,024
Liabilities
Total	1,483	2,891
Recurring \| U.S. asset backed securities
Assets
Securities available-for-sale	21,293	25,592
Recurring \| U.S. government agency mortgage-backed securities
Assets
Securities available-for-sale	5,459	4,046
Recurring \| U.S. government agency collateralized mortgage obligations
Assets
Securities available-for-sale	24,053	23,909
Recurring \| State and municipal securities
Assets
Securities available-for-sale	72,828	65,810
Recurring \| U.S. Treasuries
Assets
Securities available-for-sale	15,010
Recurring \| Non-U.S. government agencies collateralized mortgage obligations
Assets
Securities available-for-sale	999
Recurring \| Corporate bonds
Assets
Securities available-for-sale	6,507	4,205
Recurring \| Interest rate lock commitments
Assets
Derivative assets, Fair value	1,712	6,932
Liabilities
Derivative Liability	360	100
Recurring \| Forward Commitments
Assets
Derivative assets, Fair value	447
Liabilities
Derivative Liability	22	1,572
Recurring \| Customer derivatives - interest rate swaps
Assets
Derivative assets, Fair value	1,052	1,118
Liabilities
Derivative Liability	1,101	1,219
Recurring \| Level 2
Assets
Equity investments	1,011	1,031
Mortgage loans held-for-sale	117,996	229,199
Mortgage loans held-for-investment	17,142	12,182
Total	283,797	367,092
Liabilities
Total	1,123	2,791
Recurring \| Level 2 \| U.S. asset backed securities
Assets
Securities available-for-sale	21,293	25,592
Recurring \| Level 2 \| U.S. government agency mortgage-backed securities
Assets
Securities available-for-sale	5,459	4,046
Recurring \| Level 2 \| U.S. government agency collateralized mortgage obligations
Assets
Securities available-for-sale	24,053	23,909
Recurring \| Level 2 \| State and municipal securities
Assets
Securities available-for-sale	72,828	65,810
Recurring \| Level 2 \| U.S. Treasuries
Assets
Securities available-for-sale	15,010
Recurring \| Level 2 \| Non-U.S. government agencies collateralized mortgage obligations
Assets
Securities available-for-sale	999
Recurring \| Level 2 \| Corporate bonds
Assets
Securities available-for-sale	6,507	4,205
Recurring \| Level 2 \| Forward Commitments
Assets
Derivative assets, Fair value	447
Liabilities
Derivative Liability	22	1,572
Recurring \| Level 2 \| Customer derivatives - interest rate swaps
Assets
Derivative assets, Fair value	1,052	1,118
Liabilities
Derivative Liability	1,101	1,219
Recurring \| Level 3
Assets
Total	1,712	6,932
Liabilities
Total	360	100
Recurring \| Level 3 \| Interest rate lock commitments
Assets
Derivative assets, Fair value	1,712	6,932
Liabilities
Derivative Liability	$ 360	$ 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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