Represents the amount of cash outflow from dividend equivalents.

No definition available.

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Represents the performance period of RSU granted.

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No definition available.

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

+ References

No definition available.

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The number of shares reserved for future grants including all plans.

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No definition available.

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Consists of the right to receive share of common stock.

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No definition available.

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Total cost of shares repurchased divided by the total number of shares repurchased. This element is used when state law does not recognize treasury stock.

+ References

No definition available.

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Represents the percentage of shares outstanding under the repurchase plan.

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No definition available.

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- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

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Aggregate dividends declared during the period for each share of common stock outstanding.

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Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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- Definition

The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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-Topic 718

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-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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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)(3)

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(3)

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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).

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

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-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

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The weighted average fair value at grant date for nonvested equity-based awards issued 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).

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

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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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)(i)-(ii)

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

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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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)(i)-(ii)

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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)(2)

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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-SubTopic 10

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-Subparagraph (c)(2)(iii)(2)

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

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-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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- Definition

Number of share options (or share units) exercised during the current period.

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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

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-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

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-Topic 505

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-Subparagraph (SX 210.5-02.28,29)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

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Equity (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		255 Months Ended	0 Months Ended	1 Months Ended	0 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Apr. 21, 2015	Apr. 30, 2015	Mar. 27, 2015	Mar. 25, 2014	May 01, 2015
Equity
Proceed from option exercises	$ 6.1	$ 8.4
Common stock dividend quarterly declared and paid per share (in dollars per share)	$ 0.40	$ 0.35
Share Repurchase Plan
Number of shares repurchased under stock repurchase plan	3,187,235		19,400,000
Average costs per share	$ 58.02		$ 27.31
Value of shares repurchased	184.9
Weighted Average Grant Date Fair Value
Stock options exercised (in shares)	109,556
Dividends paid	31.7us-gaap_PaymentsOfDividendsCommonStock	27.1us-gaap_PaymentsOfDividendsCommonStock
Subsequent event
Share Repurchase Plan
Number of shares repurchased under stock repurchase plan					251,165
Average costs per share					$ 59.97
Value of shares repurchased					15.1
Number of shares authorized by the Board of Directors to be repurchased under stock repurchase plan								3,684,833
Shares outstanding ( as a percent)								5.00%
Weighted Average Grant Date Fair Value
Common stock quarterly dividend per share (in dollars per share)				$ 0.40
Pending settlement
Share Repurchase Plan
Number of shares repurchased under stock repurchase plan	231,626
Value of shares repurchased	13.7
Restricted stock, 2015 grant
Share Based Compensation
Restricted stock granted (in shares)						507,760
Share of common stock							1
The number of grants made during the period on the basis of service and performance criteria other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).						185,450
Changes in unvested restricted stock grants and RSUs
Granted (in shares)						507,760
Weighted Average Grant Date Fair Value
Performance targets Period						3 years
Restricted stock, 2012 grant
Weighted Average Grant Date Fair Value
Restricted stock units that vested	258,719
Restricted stock units (RSUs)
Share Based Compensation
Restricted stock granted (in shares)	557,760
Fair value of restricted stock granted (in dollars per share)	$ 59.27
Changes in unvested restricted stock grants and RSUs
Unvested at the beginning of the period (in shares)	846,760
Granted (in shares)	557,760
Vested (in shares)	(63,000)
Canceled (in shares)	(82,850)
Unvested at the end of the period (in shares)	1,258,670		1,258,670
Shares reserved for future grants (all plans)	2,356,894
Weighted Average Grant Date Fair Value
Unvested at the beginning of the period (in dollars per share)	$ 65.10
Granted (in dollars per shares)	$ 59.27
Vested (in dollars per shares)	$ 57.42
Canceled (in dollars per shares)	$ 58.66
Unvested at the end of the period (in dollars per shares)	$ 63.33		$ 63.33
Dividend equivalents	$ 1.0
Performance targets Period						3 years
Restricted stock units (RSUs) \| Time-based \| CEO
Share Based Compensation
Restricted stock granted (in shares)						10,000
Changes in unvested restricted stock grants and RSUs
Granted (in shares)						10,000
Weighted Average Grant Date Fair Value
Performance targets Period						18 months
Restricted stock units (RSUs) \| Performance-based \| CEO
Share Based Compensation
Restricted stock granted (in shares)						40,000
Changes in unvested restricted stock grants and RSUs
Granted (in shares)						40,000
Weighted Average Grant Date Fair Value
Performance targets Period						18 months