3.Changes in Accumulated Other Comprehensive Loss: Schedule of Components of Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended		12 Months Ended
	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Details
Other Comprehensive Income, Before Tax Amount	$ (161)	$ (141)	$ (43)	$ (81)	$ (161)	$ 43	$ (73)	$ (96)
Other Comprehensive Income, Taxes	34	30	14	28	34	14	16	33
Other Comprehensive Income, Net of Tax Amount	(127)	$ (111)	(29)	$ (53)	(127)	(29)	$ (57)	$ (63)
Other comprehensive loss, net, before tax amount	(20)		38		(88)	53
Unrealized holding gain arising during period, taxes	4		(14)		18	(19)
Unrealized holding gain arising during period, net of tax amount	(16)		24		(70)	34
Other comprehensive income loss, net, tax (expense) benefit	4		(14)		18	(19)
Other comprehensive income loss, net, net after tax amount	$ (16)		$ 25		$ (70)	$ 34