Fair Value Measurements and Disclosures - Financial assets measured at fair value on a recurring basis (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Assets
Securities available-for-sale	$ 90,552	$ 58,856
Mortgage loans held-for-investment	10,553	10,546
U.S. asset backed securities
Assets
Securities available-for-sale	20,661	11,866
U.S. government agency mortgage-backed securities
Assets
Securities available-for-sale	8,132	5,497
U.S. government agency collateralized mortgage obligations
Assets
Securities available-for-sale	37,342	35,223
State and municipal securities
Assets
Securities available-for-sale	24,417	6,270
Level 3 \| Interest rate lock commitments
Assets
Derivative assets, Fair value	4,021	504
Recurring
Assets
Mortgage loans held-for-sale	107,506	33,704
Mortgage loans held-for-investment	10,553	10,546
Total	214,714	105,505
Liabilities
Total	3,939	707
Recurring \| U.S. asset backed securities
Assets
Securities available-for-sale	20,661	11,866
Recurring \| U.S. government agency mortgage-backed securities
Assets
Securities available-for-sale	8,132	5,497
Recurring \| U.S. government agency collateralized mortgage obligations
Assets
Securities available-for-sale	37,342	35,223
Recurring \| State and municipal securities
Assets
Securities available-for-sale	24,417	6,270
Recurring \| Investments in mutual funds
Assets
Securities available-for-sale	1,025	1,009
Recurring \| Interest rate lock commitments
Assets
Derivative assets, Fair value	4,021	504
Liabilities
Derivative Liability	332	157
Recurring \| Forward Commitments
Assets
Derivative assets, Fair value		504
Liabilities
Derivative Liability	2,424	119
Recurring \| Customer derivatives - Interest rate swaps
Assets
Derivative assets, Fair value	1,057	382
Liabilities
Derivative Liability	1,183	431
Recurring \| Level 2
Assets
Mortgage loans held-for-sale	107,506	33,704
Mortgage loans held-for-investment	10,553	10,546
Total	210,693	104,503
Liabilities
Total	3,607	550
Recurring \| Level 2 \| U.S. asset backed securities
Assets
Securities available-for-sale	20,661	11,866
Recurring \| Level 2 \| U.S. government agency mortgage-backed securities
Assets
Securities available-for-sale	8,132	5,497
Recurring \| Level 2 \| U.S. government agency collateralized mortgage obligations
Assets
Securities available-for-sale	37,342	35,223
Recurring \| Level 2 \| State and municipal securities
Assets
Securities available-for-sale	24,417	6,270
Recurring \| Level 2 \| Investments in mutual funds
Assets
Securities available-for-sale	1,025	1,009
Recurring \| Level 2 \| Forward Commitments
Assets
Derivative assets, Fair value		6
Liabilities
Derivative Liability	2,424	119
Recurring \| Level 2 \| Customer derivatives - Interest rate swaps
Assets
Derivative assets, Fair value	1,057	382
Liabilities
Derivative Liability	1,183	431
Recurring \| Level 3
Assets
Total	4,021	504
Liabilities
Total	332	157
Recurring \| Level 3 \| Interest rate lock commitments
Assets
Derivative assets, Fair value	4,021	504
Liabilities
Derivative Liability	$ 332	$ 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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