Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

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

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ 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)(2)(iii)(1)

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- Definition

Net number of share options (or share units) granted during the period.

+ 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)(iv)(1)

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

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ 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 (d)(1)

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

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- Definition

Number of shares that have been repurchased and retired during the period.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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- Definition

Amount of a stock repurchase plan authorized by an entity's Board of Directors.

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Amount remaining of a stock repurchase plan authorized by an entity's Board of Directors.

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- Definition

The percentage of the original award that is paid out to employees at the end of the vesting period.

+ References

No definition available.

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Value of aggregate grant date fair value during the period.

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The maximum potential share payout at each balance sheet date.

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Share Capital - Narrative (Details) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	0 Months Ended		3 Months Ended	12 Months Ended
	Feb. 21, 2014	Feb. 22, 2013	Mar. 31, 2014	Dec. 31, 2013
2014 Repurchase Authorization
Shareholders Equity Disclosure [Line Items]
Stock Repurchase Program, Authorized Amount	$ 1,000,000,000
2013 Repurchase Authorization
Shareholders Equity Disclosure [Line Items]
Stock Repurchase Program, Authorized Amount		850,000,000
Stock Repurchased and Retired During Period, Shares			5.8
Stock Repurchased and Retired During Period, Value			175,000,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount	200,000,000			275,000,000
Stock options
Shareholders Equity Disclosure [Line Items]
Weighted Average Grant Date Fair Value Per Stock Option			$ 8.60
Number of Stock Options Granted During the Period			1.0
Restricted stock units
Shareholders Equity Disclosure [Line Items]
Number of Awards Granted During the Period			1.7
Aggregate Grant Date Fair Value of Award			51,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			3 years
Performance units
Shareholders Equity Disclosure [Line Items]
Number of Awards Granted During the Period			0.6
Aggregate Grant Date Fair Value of Award			$ 16,300,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			3 years
Share Based Compensation Arrangement Performance Units Maximum Share Payout Number			1.1
Minimum [Member]
Shareholders Equity Disclosure [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			3 years
Minimum [Member] \| Performance units
Shareholders Equity Disclosure [Line Items]
Performance Units Final Payout Percentage Of Grant Amount			0.00%
Maximum [Member]
Shareholders Equity Disclosure [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			4 years
Maximum [Member] \| Performance units
Shareholders Equity Disclosure [Line Items]
Performance Units Final Payout Percentage Of Grant Amount			200.00%