v2.4.0.6

Defined benefit plan (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Nov. 05, 2011
Defined Benefit Plan
Total fair value of the assets	$ 11,939	$ 10,482	$ 10,525
Canadian equity investment
Defined Benefit Plan
Total fair value of the assets	3,555	3,166
U.S. equity investment
Defined Benefit Plan
Total fair value of the assets	1,618	1,429
International equity investment
Defined Benefit Plan
Total fair value of the assets	1,658	1,383
Corporate bond investment - fixed income
Defined Benefit Plan
Total fair value of the assets	4,745	4,200
Other fixed income
Defined Benefit Plan
Total fair value of the assets	363	304
Level 2
Defined Benefit Plan
Total fair value of the assets	11,939	10,482
Level 2 | Canadian equity investment
Defined Benefit Plan
Total fair value of the assets	3,555	3,166
Level 2 | U.S. equity investment
Defined Benefit Plan
Total fair value of the assets	1,618	1,429
Level 2 | International equity investment
Defined Benefit Plan
Total fair value of the assets	1,658	1,383
Level 2 | Corporate bond investment - fixed income
Defined Benefit Plan
Total fair value of the assets	4,745	4,200
Level 2 | Other fixed income
Defined Benefit Plan
Total fair value of the assets	$ 363	$ 304

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Section 35

-Paragraph 50

-URI http://asc.fasb.org/extlink&oid=6867990&loc=d3e12355-114930



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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 87

-Paragraph 49

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph d(iv)(b)(i)

-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.



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph b

-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.



Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

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