Income tax expense (Details Narrative)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Canada
Operating Loss Carryforwards, Expiration Dates	expiration dates 2014 to 2031	expiration dates 2014 to 2031	expiration dates 2014 to 2031
US
Operating Loss Carryforwards, Expiration Dates	expiration dates 2020 to 2026	expiration dates 2020 to 2026	expiration dates 2020 to 2026

The expiration date of each operating loss carryforward included in total operating loss carryforwards, or the applicable range of such expiration dates.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 48

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration