Employee Purchase Plan Purchase Price Percentage of Fair Market Value

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- Definition

Employee Stock Purchase Plan Offered Period

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Percentage On First Anniversary

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No definition available.

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- Definition

Exercise period for outstanding stock options.

+ References

No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award, Options, Vesting Percentage in Each Quarter

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No definition available.

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- Definition

Share Based Goods And Nonemployee Services Transaction Award Award Requisite Service Period

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No definition available.

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- Definition

Share-Based Goods and Nonemployee Services Transaction, Options, Percentage Vested for initial appointment grant.

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No definition available.

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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)

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- Definition

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

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-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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

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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

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-Section 50

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

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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)

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- Definition

Period from grant date that an equity-based award expires, 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

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-SubTopic 10

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-Paragraph 2

-Subparagraph (a)(2)

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- Definition

Expected term of share-based compensation awards, 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 S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.D.2)

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section D

-Subsection 2

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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-Name Accounting Standards Codification

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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).

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-Publisher FASB

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-Topic 718

-SubTopic 10

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-Paragraph 2

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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.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(2)

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- Definition

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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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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.

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-Publisher FASB

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

+ Details

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- Definition

The maximum number of shares (or other type of equity) that have been approved for issuance in the equity-based payment transaction.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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Aggregate value of stock related to Restricted Stock Awards issued during the period.

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Stock Incentive Plans - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	1 Months Ended		12 Months Ended			1 Months Ended	0 Months Ended	1 Months Ended
	May 31, 2011	Oct. 31, 2010	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 31, 2012	Dec. 17, 2014	Jun. 30, 2009	Jun. 30, 2013	Jun. 30, 2010	Dec. 31, 2004
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive plan, shares available for future grant			9,317,147
Option vesting percentage on the first anniversary of grant date			25.00%
Option vesting percentage at the end of each successive three-month period			6.25%
Stock options granted			1,352,000
Weighted average fair value of stock options granted			$ 8.68	$ 8.68	$ 8.68
Aggregate intrinsic value of stock option exercised			$ 126.5	$ 57.9	$ 4.8
Stock options granted, exercise price			$ 75.77
Restricted Stock Awards Granted			29,000
Fair value of equity awards granted	2.3	1.4
Employee stock purchase plan, offering period			6 months
Weighted average fair value awards granted			$ 68.28
Expected volatility					57.00%
Expected option life				5 years 7 months 6 days
Current Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of equity awards granted						5.3
Stock Incentive Plan 2004
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive plan, shares authorized			12,366,485
Performance Contingent Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted			612,085				612,085
Stock options granted, exercise price							$ 96.45
Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock Awards Granted		113,370
Stock awards vesting period		3 years
Total fair value of restricted stock awards vested during period			44.4	5.8	1.5
Restricted stock awards \| Current Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock Awards Granted						508,928
Stock awards vesting period						2 years
Stock Incentive Plan 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive plan, shares authorized								2,200,000	5,900,000
Stock incentive plan, non-employee directors award vest on each first, second and third anniversary of grant date								33.333%
Stock Incentive Plan 2009 \| Board of Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive plan, non-employee directors required service period								6 months
Stock Incentive Plan 2009 \| Board of Directors \| Initial Appointment
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive plan, shares authorized for non-employee directors								30,000
Stock Incentive Plan 2009 \| Board of Directors \| On Date Of Annual Meeting Of Shareholders
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive plan, shares authorized for non-employee directors								15,000
Stock Incentive Plan 2009 \| If non-employee Director has less than five years of service \| Amendment \| Board of Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise period on any outstanding stock option awards			3 months
Stock Incentive Plan 2009 \| If non-employee Director has five or more years of service \| Amendment \| Board of Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise period on any outstanding stock option awards			5 years
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive plan, shares available for future grant			8,168,533
Equity awards, term			10 years
Additional Equity Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive plan, shares available for future grant			941,583
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive plan, shares authorized										715,789	315,789
Stock incentive plan, shares available for future grant			207,031
Employee stock purchase plan, purchase price as a percentage of common stock closing price			85.00%
Employee stock purchase plan, shares issued			21,938	45,141	73,590
Weighted average fair value awards granted			$ 17.03	$ 11.49	$ 2.82
Expected volatility			55.00%	55.00%	55.00%
Expected option life			6 months	6 months	6 months
Risk-free interest rate			0.10%	0.10%	0.10%
Performance-based Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted			194,000
Weighted average fair value of stock options granted				$ 32.26
Aggregate intrinsic value of stock option exercised			$ 0.1
Stock options granted, exercise price			$ 96.45
Performance Based Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards, term	5 years
Restricted Stock Awards Granted	229,806