13. Income taxes (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Tax Disclosure [Abstract]
Effective Income Tax Rate Reconciliation, Percent	24.40%	35.20%	33.30%	24.40%
Other Income Tax Expense (Benefit), Continuing Operations	$ 224,000
Other Tax Expense (Benefit)	220,000
Tax Credit Carryforward, Expiration Dates		$67,000
Income (Loss) from Continuing Operations before Income Taxes, Foreign		92,000	68,000	(29,000)
Deferred Tax Assets, Valuation Allowance	242,000	216,000
Unrecognized Tax Benefits	106,000	251,000	228,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued		106,000
Income Tax Examination, Penalties and Interest Accrued		$ 46,000	$ 10,000