12. Stock incentive plans (Tables)

12 Months Ended

Dec. 31, 2014

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	Year ended December 31,
	2014		2013		2012
Expected option term	6.6 years		6.8 years		6.7 years
Expected volatility		53.8%		56.5%		57.8%
Risk-free interest rate		1.6%		0.8%		0.8%
Dividend yield		2.6%		3.1%		-%

Schedule of Share-based Compensation, Activity [Table Text Block]

	Number of Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term	Aggregate Intrinsic Value
Outstanding at December 31, 2013		718,475	$	8.49
Granted		169,500		11.11
Exercised		(6,000)		2.18
Forfeited		(62,500)		8.51
Expired		(23,500)		31.58
Outstanding at December 31, 2014		795,975	$	8.41	5.7 years	$	87,000
Options exercisable at December 31, 2014		490,725	$	7.72	4.1 years	$	87,000
Options vested or expected to vest		784,108	$	8.39	6.0 years	$	87,000