Share-based compensation(Tables)

12 Months Ended

Dec. 31, 2017

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

Details of the stock option transactions for the years ended December 31, 2017, 2016 and 2015 are summarized as follows:

	Number		Weighted average exercise price (CAD$)		Weighted average remaining contractual life (years)		Aggregate intrinsic value (CAD$)
Outstanding as at December 31, 2014		1,278,290		4.68		3.34		8,411

Options granted		382,900		10.84
Options exercised		(129,236)		3.76
Options forfeited		(45,097)		8.76
Options expired		(14,260)		4,169
Outstanding as at December 31, 2015		1,472,597		5.88		2.88		8,024

Options granted		617,500		5.97
Options forfeited		(72,200)		4.94
Options expired		(16,340)		20.22
Outstanding as at December 31, 2016		2,001,557		5.82		2.72		1,110

Options granted		1,242,500		4.16
Options exercised		(324,000)		2.16
Options forfeited		(20,000)		5.10
Options expired		(8,000)		1.70
Outstanding as at December 31, 2017		2,892,057		5.52		3.07		69
Exercisable as at December 31, 2017		1,855,368		5.90		2.55		69

Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block]

At December 31, 2017, stock options to executive officers and directors, employees and consultants were outstanding as follows:

	Options outstanding						Options exercisable
			Weighted		Weighted				Weighted
			average		average				average
			remaining		exercise				exercise
Range of			contractual		price				price
exercise prices (CAD$)	Number		life (years)		(CAD$)		Number		(CAD$)

$1.65 to $2.08		277,000		0.22		1.66		277,000		1.66
$2.09 to $5.63		1,477,183		3.86		4.26		703,557		4.39
$5.64 to $7.37		550,000		3.47		6.14		325,667		6.14
$7.38 to $13.09		587,874		2.07		9.91		549,144		9.92

		2,892,057		3.07		5.52		1,855,368		5.90

Schedule Of Nonvested Option Activity [Table Text Block]

A summary of the Company’s non-vested stock option activity and related information for the year ended December 31, 2017 is as follows:

	Number		Weighted average
	of		grant-date fair value
Non-vested options	options		(U.S.$)

Non-vested at December 31, 2016		708,588		2.27
Granted		1,242,500		1.53
Vested		(911,039)		1.90
Forfeited		(3,360)		0.04

Non-vested at December 31, 2017		1,036,689		1.69

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

The estimated fair value of the stock options granted was determined using the Black-Scholes option pricing model with the following weighted-average assumptions:

	December 31, 2017			December 31, 2016			December 31, 2015

Dividend yield		-			-			-
Expected volatility		63.7	%		65.7	%		78.4	%
Risk-free interest rate		1.2	%		0.7	%		0.6	%
Expected average life of the options		3.8 years			3.1 years			3.4 years
Estimated forfeiture rate		-			-			-

Schedule of Nonvested Restricted Stock Units Activity [Table Text Block]

Details of RSU transactions for the years ended December 31, 2017, 2016 and 2015 are summarized as follows:

	Number		Weighted average grant date fair value (USD$)		Weighted average remaining contractual life (years)		Aggregate intrinsic value (USD$)
Outstanding at December 31, 2014		-	$	-		-	$	-

RSUs granted		160,598		9.10				1,181
RSUs vested		(10,990)		9.95				89
RSUs forfeited		(17,500)		9.95
Outstanding as at December 31, 2015		132,108	$	8.91		2.16	$	1,058

RSUs granted		50,782		4.43				218
RSUs vested		(49,682)		9.03				205
RSUs forfeited		(13,505)		9.00
Outstanding as at December 31, 2016		119,703	$	6.95		1.71	$	334

RSUs granted		52,962		3.46				194
RSUs vested		(57,003)		7.59				174
RSUs forfeited		(18,706)		6.21
Outstanding as at December 31, 2017		96,956	$	4.83		1.68	$	147