Income taxes (Schedule of Components of Income Tax Expense (Benefit)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Current:
US Federal
US State
Foreign
Total current benefit
Deferred:
US Federal		117
US State		26
Foreign
Total deferred benefit		143
Total benefit for income taxes		$ 143