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Loans Receivable: Schedule of Accounts, Notes, Loans and Financing Receivable (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Loans receivable	$ 1,066,301		$ 1,037,429
Deferred loan fees, net	568		1,178
ALLL	13,057		13,347
Loans receivable, net	1,052,676		1,022,904
One-to-four family, residential, owner occupied
Loans receivable	201,989		194,141
One to four family residential non owner occupied
Loans receivable	159,267		147,825
One to Four Family
Loans receivable	361,256		341,966
One to four family residential
ALLL	3,085	$ 3,032	3,387	$ 3,265	$ 3,237	$ 2,837
Multifamily
Loans receivable	161,460		169,355
ALLL	1,643	1,579	1,680	1,928	1,884	1,820
Commercial Real Estate
Loans receivable	384,202		373,798
ALLL	4,607	4,809	4,777	4,494	4,490	4,418
Construction/Land Development One-to-four family residential
Loans receivable	45,953		51,747
Construction Land Development Multifamily
Loans receivable	37,032		40,502
Construction Land Development Commercial [Member]
Loans receivable	13,793		9,976
Construction Land Development Land Development
Loans receivable	8,356		6,629
Construction Land Development
Loans receivable	105,134		108,854
ALLL	2,271	3,132	2,331	2,121	2,454	2,816
Business
Loans receivable	36,358		30,486
ALLL	1,120	1,030	936	674	740	694
Consumer
Loans receivable	17,891		12,970
ALLL	331	226	236	272	331	297
Property total
ALLL	$ 13,057	$ 13,808	$ 13,347	$ 12,754	$ 13,136	$ 12,882