Loans Receivable Held for Investment - Risk Category of Loans by Loan Type (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Credit Quality Indicators
Loans receivable	$ 356,113	$ 358,485
Single family
Credit Quality Indicators
Loans receivable	85,391	92,177
Multi-family
Credit Quality Indicators
Loans receivable	239,900	233,309
Commercial real estate
Credit Quality Indicators
Loans receivable	6,436	5,800
Church
Credit Quality Indicators
Loans receivable	21,868	25,096
Construction
Credit Quality Indicators
Loans receivable	2,242	1,872
Commercial - other
Credit Quality Indicators
Loans receivable	264	226
Consumer
Credit Quality Indicators
Loans receivable	12	5
Pass
Credit Quality Indicators
Loans receivable	350,132	352,291
Pass | Single family
Credit Quality Indicators
Loans receivable	85,348	92,132
Pass | Multi-family
Credit Quality Indicators
Loans receivable	238,714	232,642
Pass | Commercial real estate
Credit Quality Indicators
Loans receivable	6,436	5,800
Pass | Church
Credit Quality Indicators
Loans receivable	17,179	19,678
Pass | Construction
Credit Quality Indicators
Loans receivable	2,242	1,872
Pass | Commercial - other
Credit Quality Indicators
Loans receivable	201	162
Pass | Consumer
Credit Quality Indicators
Loans receivable	12	5
Watch
Credit Quality Indicators
Loans receivable	418	672
Watch | Church
Credit Quality Indicators
Loans receivable	418	672
Special Mention
Credit Quality Indicators
Loans receivable	787	35
Special Mention | Single family
Credit Quality Indicators
Loans receivable		35
Special Mention | Multi-family
Credit Quality Indicators
Loans receivable	532
Special Mention | Church
Credit Quality Indicators
Loans receivable	255
Substandard
Credit Quality Indicators
Loans receivable	4,776	5,487
Substandard | Single family
Credit Quality Indicators
Loans receivable	43	10
Substandard | Multi-family
Credit Quality Indicators
Loans receivable	654	667
Substandard | Church
Credit Quality Indicators
Loans receivable	4,016	4,746
Substandard | Commercial - other
Credit Quality Indicators
Loans receivable	$ 63	$ 64