Summarized Information About Incentive Share, Deferred Share and Restricted Stock Units (Detail)	12 Months Ended
Dec. 31, 2013
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding at January 1, 2013	8,943,104
Granted	1,654,540
Exercised	(1,841,408)
Forfeited and cancelled	(41,382)
Outstanding at December 31, 2013	8,714,854
Deferred Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding at January 1, 2013	85,505
Granted	12,731
Outstanding at December 31, 2013	98,236

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Number of non-option equity instruments exercised by participants.

+ References

+ Details

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- Definition

Number of shares under non-option equity instrument agreements that were either cancelled or expired.

+ References

+ Details

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- Definition

Net number of non-option equity instruments granted to participants.

+ References

+ Details

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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