Note 7 - Employee Retirement Benefit Plans: Schedule of Costs of Retirement Plans, changes in benefit obligation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Text Block [Abstract]
Projected benefit obligation as of beginning of the year	$ 4,222	$ 4,650
Interest cost	148	136
Actuarial loss (gain)	284	(119)
Benefits paid	(387)	(445)
Projected benefit obligation as of beginning of the year	4,267	4,222
Contributions	386	445
Fair value of plan assets - end of year	$ 0	$ 0