Loans Receivable: Financing Receivables, Aging of loans (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Financing Receivable, 90 Days or More Past Due, Still Accruing	$ 0	$ 0
Total Loans	1,066,301,000	1,037,429,000
One-to-four family, residential, owner occupied
Total	184,000	495,000
Current	201,805,000	193,646,000
Total Loans	201,989,000	194,141,000
One to four family residential non owner occupied
Total	0	0
Current	159,267,000	147,825,000
Total Loans	159,267,000	147,825,000
Multifamily
Total	0	0
Current	161,460,000	169,355,000
Total Loans	161,460,000	169,355,000
Commercial Real Estate
Total	0	326,000
Current	384,202,000	373,472,000
Total Loans	384,202,000	373,798,000
Construction Land Development
Total	0	0
Current	105,134,000	108,854,000
Total Loans	105,134,000	108,854,000
Real Estate, Total
Total	184,000	821,000
Current	1,011,868,000	993,152,000
Total Loans	1,012,052,000	993,973,000
Business
Total	0	0
Current	36,358,000	30,486,000
Total Loans	36,358,000	30,486,000
Consumer
Total	43,000	0
Current	17,848,000	12,970,000
Total Loans	17,891,000	12,970,000
Property total
Total	227,000	821,000
Current	1,066,074,000	1,036,608,000
Total Loans	1,066,301,000	1,037,429,000
Financial Asset, 30 to 59 Days Past Due [Member] | One-to-four family, residential, owner occupied
Total	184,000	223,000
Financial Asset, 30 to 59 Days Past Due [Member] | One to four family residential non owner occupied
Total	0	0
Financial Asset, 30 to 59 Days Past Due [Member] | Multifamily
Total	0	0
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Real Estate
Total	0	0
Financial Asset, 30 to 59 Days Past Due [Member] | Construction Land Development
Total	0	0
Financial Asset, 30 to 59 Days Past Due [Member] | Real Estate, Total
Total	184,000	223,000
Financial Asset, 30 to 59 Days Past Due [Member] | Business
Total	0	0
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer
Total	43,000	0
Financial Asset, 30 to 59 Days Past Due [Member] | Property total
Total	227,000	223,000
Financial Asset, 60 to 89 Days Past Due [Member] | One-to-four family, residential, owner occupied
Total	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | One to four family residential non owner occupied
Total	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Multifamily
Total	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Real Estate
Total	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Construction Land Development
Total	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Real Estate, Total
Total	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Business
Total	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer
Total	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Property total
Total	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | One-to-four family, residential, owner occupied
Total	0	272,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | One to four family residential non owner occupied
Total	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Multifamily
Total	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Real Estate
Total	0	326,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Construction Land Development
Total	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Real Estate, Total
Total	0	598,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Business
Total	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer
Total	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Property total
Total	$ 0	$ 598,000