Noncash Share-based Compensation (Details) (USD $)	3 Months Ended
Mar. 31, 2014
Noncash Share-based Compensation (Narrative) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized	900,000
Shares reserved for issuance under Plan	8,168,000
Shares available for future grants	934,442
Unrecognized compensation cost related to share-based compensation	$ 60,900,000
Weighted average period to recognize cost, in years	2 years 10 months 27 days
Share-based compensation arrangement by share-based payment, Minimum Employee Subscription rate	1.00%
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	10.00%
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Offering Date	5.00%
Maximum Amount Contributable by employees under ESPP- Half yearly	5,000
Maximum Amount Contributable By Employees Under ESPP- Annually	10,000
ESPP contributions by Employees	$ 200,000
RSUs
Noncash Share-based Compensation (Narrative) [Line Items]
Awards, other than options, granted in period	793,070
Weighted average grant date fair value, per share, of awards granted in period	$ 35.69
MSUs
Noncash Share-based Compensation (Narrative) [Line Items]
Awards, other than options, granted in period	185,600
Weighted average grant date fair value, per share, of awards granted in period	$ 49.50
Employee Stock [Member]
Noncash Share-based Compensation (Narrative) [Line Items]
Shares reserved for issuance under Plan	500,000

ESPP contributions by Employees

No definition available.

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- Definition

Maximum Amount Contributable By Employees Under ESPP- Annually

+ References

No definition available.

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- Definition

Maximum Amount Contributable by employees under ESPP- Half yearly

+ References

No definition available.

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- Definition

Share-based compensation arrangement by share-based payment, Minimum Employee Subscription rate

+ References

No definition available.

+ Details

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- 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

Discount rate from fair value on offering date that participants pay for shares.

+ 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

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)

-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

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

+ Details

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

+ Details

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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

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