Loans Receivable: Financing Receivables, Aging of loans (Details) - USD ($)
Dec. 31, 2016
Dec. 31, 2015
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing $ 0 $ 0
Total 473,000 1,258,000
Current 827,688,000 696,158,000
Total Loans [2],[3] 828,161,000 [1] 697,416,000 [4]
One-to-four family, residential, owner occupied    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 473,000 1,161,000
Current 137,361,000 146,068,000
Total Loans 137,834,000 [1],[2] 147,229,000 [3],[4]
One-to-four family residential non-owner occupied    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Current 111,601,000 106,543,000
Total Loans 111,601,000 [1],[2] 106,543,000 [3],[4]
Multifamily    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Current 123,250,000 122,747,000
Total Loans 123,250,000 [1],[2] 122,747,000 [3],[4]
Commercial Real Estate    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Current 303,694,000 244,211,000
Total Loans 303,694,000 [1],[2] 244,211,000 [3],[4]
Construction Land Development    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Current 136,922,000 62,103,000
Total Loans 136,922,000 [1],[2] 62,103,000 [3],[4]
Real Estate, Total    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 473,000 1,161,000
Current 812,828,000 681,672,000
Total Loans 813,301,000 [1],[2] 682,833,000 [3],[4]
Business    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Current 7,938,000 7,604,000
Total Loans 7,938,000 [1],[2] 7,604,000 [3],[4]
Consumer    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 97,000
Current 6,922,000 6,882,000
Total Loans 6,922,000 [1],[2] 6,979,000 [3],[4]
Financing Receivables, 30 to 59 Days Past Due [Member]    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 304,000 678,000
Financing Receivables, 30 to 59 Days Past Due [Member] | One-to-four family, residential, owner occupied    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 304,000 678,000
Financing Receivables, 30 to 59 Days Past Due [Member] | One-to-four family residential non-owner occupied    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Financing Receivables, 30 to 59 Days Past Due [Member] | Multifamily    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Real Estate    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Financing Receivables, 30 to 59 Days Past Due [Member] | Construction Land Development    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Financing Receivables, 30 to 59 Days Past Due [Member] | Real Estate, Total    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 304,000 678,000
Financing Receivables, 30 to 59 Days Past Due [Member] | Business    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Financing Receivables, 30 to 59 Days Past Due [Member] | Consumer    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Financing Receivables, 60 to 89 Days Past Due [Member]    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 561,000
Financing Receivables, 60 to 89 Days Past Due [Member] | One-to-four family, residential, owner occupied    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 483,000
Financing Receivables, 60 to 89 Days Past Due [Member] | One-to-four family residential non-owner occupied    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Multifamily    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Real Estate    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Construction Land Development    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Real Estate, Total    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 483,000
Financing Receivables, 60 to 89 Days Past Due [Member] | Business    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Consumer    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 78,000
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 169,000 19,000
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | One-to-four family, residential, owner occupied    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 169,000 0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | One-to-four family residential non-owner occupied    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Multifamily    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Real Estate    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Construction Land Development    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Real Estate, Total    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 169,000 0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Business    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total 0 0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Consumer    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Total $ 0 $ 19,000
[1] (1) There were no loans 90 days past due and still accruing interest at December 31, 2015.
[2] (2) Net of LIP.
[3] Net of LIP.
[4] (1) There were no loans 90 days past due and still accruing interest at December 31, 2016.