Number of Shares for Each Full Value Award

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- Definition

The percentage of shares expected to vest in the calculation for unrecognized compensation cost and compensation expense.

+ References

No definition available.

+ Details

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- Definition

Percentage of Stock-based Awards Possible to be Earned

+ References

No definition available.

+ Details

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- Definition

Total Duration of the Stock Incentive Plan

+ References

No definition available.

+ Details

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ 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 (i)

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

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

+ Details

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- Definition

The total cash inflow associated with the amount received from holders to acquire the entity's shares under incentive and share awards, including stock option exercises. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (a)

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

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- Definition

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.

+ 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 (a)(1)

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

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- Definition

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).

+ 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)

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

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ 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)(2)

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

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ 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 (a)(3)

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

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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

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- Definition

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

+ References

No definition available.

+ Details

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Stock-Based Compensation - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award
Cash Received Under Share-based Payment Arrangements	$ 12.3	$ 11.4	$ 4.9
Stock Incentive Plan 2012
Share-based Compensation Arrangement by Share-based Payment Award
Number of Shares Authorized	20,000,000
Number of Shares for Each Full Value Award	1.76
Total Duration of the Stock Incentive Plan	8 years
Award Vesting Period	3 years
Number of Shares Available for Grant	17,050,000
Stock Incentive Plan 2007
Share-based Compensation Arrangement by Share-based Payment Award
Number of Shares Authorized	35,000,000
Number of Shares for Each Full Value Award	2.7
Total Duration of the Stock Incentive Plan	8 years
Award Vesting Period	3 years
Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award
Award Vesting Period	3 years
Weighted Average Grant Date Fair Value of Shares Granted	$ 34.72	$ 25.26
Compensation Cost Not yet Recognized	5.2
Period for Recognition of Compensation Cost Not Yet Recognized	1 year 272 days
Percentage Stock-based Awards Expected to Vest	100.00%
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award
Weighted Average Grant Date Fair Value of Shares Granted	$ 33.77	$ 24.68	$ 22.96
Compensation Cost Not yet Recognized	10.9
Period for Recognition of Compensation Cost Not Yet Recognized	292 days
Fair Value of Awards Vested During the Period	19.8	18.3	19.5
Cash Settled Awards
Share-based Compensation Arrangement by Share-based Payment Award
Weighted Average Grant Date Fair Value of Shares Granted	$ 33.85	$ 24.22	$ 23.23
Compensation Cost Not yet Recognized	0
Fair Value of Awards Vested During the Period	2.1	2.4	1.5
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Period for Recognition of Compensation Cost Not Yet Recognized	0 years 110 days
Stock Option Compensation Not yet Recognized	$ 0.2
Options Granted	0.00
Minimum \| Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award
Percentage of Stock-based Awards Possible to be Earned	0.00%
Minimum \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award
Award Vesting Period	1 year
Minimum \| Cash Settled Awards
Share-based Compensation Arrangement by Share-based Payment Award
Award Vesting Period	1 year
Minimum \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Award Vesting Period	1 year
Maximum \| Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award
Percentage of Stock-based Awards Possible to be Earned	180.00%
Maximum \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award
Award Vesting Period	3 years
Maximum \| Cash Settled Awards
Share-based Compensation Arrangement by Share-based Payment Award
Award Vesting Period	3 years
Maximum \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Award Vesting Period	3 years