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Contingencies - Additional Information (Detail) CAD in Millions	1 Months Ended	12 Months Ended
	Jun. 30, 2016 CAD Officers	Dec. 31, 2016 CAD Subsidiary
Loss Contingencies [Line Items]
Amount related to damages | CAD	CAD 1,800	CAD 2,560
KS Centoco Ltd [Member]
Loss Contingencies [Line Items]
Number of subsidiaries sued by KS Centoco Ltd | Subsidiary		2
Percentage of equity interest owned by Company		23.00%
Percentage of equity interest owned by third party		77.00%
Number of officers sued | Officers	2
MST Automotive Inc [Member]
Loss Contingencies [Line Items]
Percentage of equity interest owned by Company		77.00%
Percentage of equity interest owned by third party		23.00%

X

- Definition

Number Of Officers

+ References

No definition available.

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- Definition

Number of subsidiaries sued.

+ References

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- Definition

Percentage of equity interest owned by company.

+ References

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- Definition

Percentage of equity interest owned by third party.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

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- Details

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- Details

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