Share Capital - Impact on Results of Operations of Recording DSU Compensation Expense (Detail) (Deferred Share Units [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Deferred share unit compensation expense	$ (26)	$ 59	$ 145	$ 89
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Deferred share unit compensation expense	(10)	22	43	33
Selling, General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Deferred share unit compensation expense	$ (16)	$ 37	$ 102	$ 56