13. Income taxes (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Effective Income Tax Rate Reconciliation, Percent	37.20%	24.40%	35.20%
Unrecognized Tax Benefits, Income Tax Penalties Accrued		$ 224,000
Unrecognized Tax Benefits	124,000	106,000	220,000
Deferred Tax Assets, Tax Credit Carryforwards, Research	104,000	68,000
Deferred Tax Assets, Tax Credit Carryforwards	3,000
Income (Loss) from Continuing Operations before Income Taxes, Foreign	(56,000)	(29,000)	92,000
Deferred Tax Assets, Valuation Allowance	282,000	242,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	124,000
Income Tax Examination, Penalties and Interest Accrued	$ 20,000	$ 10,000