Loans Held for Investment - Company's Investment in Impaired Loans (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Impaired Loans
Unpaid Principal Balance	$ 12,739,000			$ 12,739,000		$ 6,896,000
Total impaired loans	7,268,000			7,268,000		3,284,000
With Specific Allowance	488,000			488,000		97,000
Without Specific Allowance	6,780,000			6,780,000		3,187,000
Specific Allowance for Impaired Loans	250,000		$ 0	250,000	$ 0	55,000
Average Recorded Investment	6,456,000	$ 7,402,000	1,157,000	7,234,000	819,000
Interest Income Recognized	0	0	22,000	0	47,000
Business loans \| Commercial and industrial
Impaired Loans
Unpaid Principal Balance	1,515,000			1,515,000		1,585,000
Total impaired loans	1,027,000			1,027,000		1,160,000
With Specific Allowance	0			0		0
Without Specific Allowance	1,027,000			1,027,000		1,160,000
Specific Allowance for Impaired Loans	0		0	0	0	0
Average Recorded Investment	1,030,000	1,272,000	446,000	1,161,000	218,000
Interest Income Recognized	0	0	7,000	0	12,000
Business loans \| Franchise
Impaired Loans
Unpaid Principal Balance	205,000			205,000
Total impaired loans	209,000			209,000
With Specific Allowance	0			0
Without Specific Allowance	209,000			209,000
Specific Allowance for Impaired Loans	0		0	0	0
Average Recorded Investment	209,000	70,000	0	93,000	0
Interest Income Recognized	0	0	0	0	0
Business loans \| Commercial owner occupied
Impaired Loans
Unpaid Principal Balance						98,000
Total impaired loans						97,000
With Specific Allowance						97,000
Without Specific Allowance						0
Specific Allowance for Impaired Loans	0		0	0	0	55,000
Average Recorded Investment	0	2,317,000	170,000	1,931,000	162,000
Interest Income Recognized	0	0	3,000	0	8,000
Business loans \| SBA
Impaired Loans
Unpaid Principal Balance	7,618,000			7,618,000		4,329,000
Total impaired loans	2,748,000			2,748,000		1,201,000
With Specific Allowance	488,000			488,000		0
Without Specific Allowance	2,260,000			2,260,000		1,201,000
Specific Allowance for Impaired Loans	250,000		0	250,000	0	0
Average Recorded Investment	1,914,000	1,360,000	85,000	1,505,000	204,000
Interest Income Recognized	0	0	2,000	0	10,000
Real estate loans \| Commercial non-owner occupied
Impaired Loans
Unpaid Principal Balance	1,287,000			1,287,000
Total impaired loans	1,290,000			1,290,000
With Specific Allowance	0			0
Without Specific Allowance	1,290,000			1,290,000
Specific Allowance for Impaired Loans	0		0	0	0
Average Recorded Investment	1,290,000	430,000	342,000	573,000	114,000
Interest Income Recognized	0	0	7,000	0	7,000
Real estate loans \| Multi-family
Impaired Loans
Unpaid Principal Balance	589,000			589,000
Total impaired loans	589,000			589,000
With Specific Allowance	0			0
Without Specific Allowance	589,000			589,000
Specific Allowance for Impaired Loans	0		0	0	0
Average Recorded Investment	589,000	589,000	0	666,000	0
Interest Income Recognized	0	0	0	0	0
Real estate loans \| One-to-four family
Impaired Loans
Unpaid Principal Balance	1,476,000			1,476,000		849,000
Total impaired loans	1,388,000			1,388,000		817,000
With Specific Allowance	0			0		0
Without Specific Allowance	1,388,000			1,388,000		817,000
Specific Allowance for Impaired Loans	0		0	0	0	0
Average Recorded Investment	1,406,000	1,343,000	103,000	1,258,000	108,000
Interest Income Recognized	0	0	3,000	0	9,000
Real estate loans \| Land
Impaired Loans
Unpaid Principal Balance	34,000			34,000		35,000
Total impaired loans	4,000			4,000		9,000
With Specific Allowance	0			0		0
Without Specific Allowance	4,000			4,000		9,000
Specific Allowance for Impaired Loans	0		0	0	0	$ 0
Average Recorded Investment	5,000	6,000	11,000	6,000	13,000
Interest Income Recognized	0	0	0	0	1,000
Consumer Loans \| Consumer loans
Impaired Loans
Unpaid Principal Balance	15,000			15,000
Total impaired loans	13,000			13,000
With Specific Allowance	0			0
Without Specific Allowance	13,000			13,000
Specific Allowance for Impaired Loans	0		0	0	0
Average Recorded Investment	13,000	15,000	0	41,000	0
Interest Income Recognized	$ 0	$ 0	$ 0	$ 0	$ 0

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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