8. Fair Value: Fair Value Measurements, Nonrecurring (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Impaired Loans
Assets, Fair Value Disclosure, Nonrecurring	$ 174	$ 134
Other Real Estate Owned
Assets, Fair Value Disclosure, Nonrecurring	569	626
Level 1 | Impaired Loans
Assets, Fair Value Disclosure, Nonrecurring		0
Level 1 | Other Real Estate Owned
Assets, Fair Value Disclosure, Nonrecurring	0	0
Level 2 | Impaired Loans
Assets, Fair Value Disclosure, Nonrecurring		0
Level 2 | Other Real Estate Owned
Assets, Fair Value Disclosure, Nonrecurring	0	0
Level 3 | Impaired Loans
Assets, Fair Value Disclosure, Nonrecurring	174	134
Level 3 | Other Real Estate Owned
Assets, Fair Value Disclosure, Nonrecurring	$ 569	$ 626