Stock Based Compensation - Summary of Option Activity (Details) (Third Amended and Restated 1997 Stock Option Plan, Stock Options, CAD) In Thousands, except Share data, unless otherwise specified	9 Months Ended		12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Third Amended and Restated 1997 Stock Option Plan | Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options outstanding as of December 31, 2011 (options)	8,539,000
Options granted (options)	5,054,000	1,988,000
Options exercised (options)	(138,000)
Options forfeited, canceled and expired (options)	(963,000)
Options outstanding as of September 30, 2012 (options)	12,492,000		8,539,000
Options exercisable as of March 31, 2012	8,057,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Options outstanding as of December 31, 2011 - Weighted average exercise price	3.18
Options granted - Weighted average exercise price	1.97
Options exercised - Weighted average exercise price	1.36
Options forfeited, canceled and expired - Weighted average exercise price	2.89
Options outstanding as of September 30, 20012 - Weighted average exercise price	2.73		3.18
Options exercisable as of March 30, 2012 - Weighted average exercise price exercisable	3.00
Share Based Compensation Arrangement By Share Based Payment Award, Options Outstanding, Weighted Average RemainingTerm, Rollforward [Roll Forward]
Options outstanding as of December 31, 2011 - Aggregate intrinsic value	95
Options granted in period - Aggregate intrinsic value	0
Options exercised - Aggregate intrinsic value	101
Options forfeited, canceled and expired - Aggegrate intrinsic value	0
Options outstanding as of September 30, 2012 - Aggregate intrinsic value	767		95
Share Based Compensation Arrangement By Share Based Payment Award, Options Outstanding, Weighted Average Remaining Contractual Term, Rollforward [Roll Forward]
Options outstanding as of December 31, 2011 - Weighted average remaining contractual term	6 years 4 months 24 days		7 years
Options granted - Weighted average remaining contractual term	5 years 10 months 24 days
Options exercised - Weighted average remaining contractual term	2 years 7 months 6 days
Options forfeited, canceled and expired - Weighted average remaining contractual term	6 years 7 months 6 days
Options outstanding as of September 30, 2012 - Weighted average remaining contractual term	6 years 4 months 24 days		7 years
Options exercisable as of September 30, 2012 - Weighted average remaining contractual term	5 years 10 months 24 days
Options exercisable - Aggregate intrinsic value	527