Percent of Shares Outstanding to Increase Number of Shares Available for Grant and Issuance

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Shares Held Subject to Repurchase

+ References

No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable within one year (or the operating cycle, if longer).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ 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 share-based awards, other than options, awarded to employees as compensation.

+ References

No definition available.

+ Details

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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

Intrinsic value of equity-based compensation awards not vested. Excludes stock and unit options.

+ References

No definition available.

+ Details

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- Definition

Per share weighted average intrinsic value of equity-based compensation awards not vested. Excludes stock and unit options.

+ 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)(i)-(ii)

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

+ Details

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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

+ Details

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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.

+ 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 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

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

+ 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)

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

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

+ Details

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- Definition

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

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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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Stock-Based Compensation - Narrative (Details) (USD $)	3 Months Ended	9 Months Ended		3 Months Ended				3 Months Ended			9 Months Ended	3 Months Ended	9 Months Ended		9 Months Ended		9 Months Ended
Stock-Based Compensation - Narrative (Details) (USD $)	Sep. 30, 2014	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014 2014 Plan	Apr. 30, 2014 2014 Plan	Sep. 30, 2014 2014 Plan Maximum	Apr. 30, 2014 2014 Plan Maximum	Sep. 30, 2014 2014 Employee Stock Purchase Plan	Apr. 30, 2014 2014 Employee Stock Purchase Plan	Sep. 30, 2014 2014 Employee Stock Purchase Plan Maximum	Sep. 30, 2014 Stock Option	Sep. 30, 2014 Stock Option Common Stock	Sep. 30, 2014 Restricted Stock Award	Dec. 31, 2013 Restricted Stock Award	Sep. 30, 2014 ESPP	Dec. 31, 2013 ESPP	Sep. 30, 2014 Restricted Stock Units (RSUs)	Sep. 30, 2014 Restricted Stock Units (RSUs) 2011 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price as percent of fair value of common stock																		100.00%
Common stock reserved for issuance (in shares)	27,077,000	27,077,000	48,137,000		6,510,000		20,025,189		651,000						651,000	0
Percent of shares outstanding to increase number of shares available for grant and issuance				3.00%				1.00%
Number of shares available for grant	12,447,000	12,447,000	8,941,000			12,500,000				2,500,000
Unrecognized stock-based compensation expense for unvested options, net of expected forfeitures															$ 4,100,000		$ 3,400,000
Weighted-average grant-date fair value of options granted (usd per share)		$ 20.45
Aggregate intrinsic value of options exercised		7,500,000
Unrecognized stock-based compensation expense	88,800,000	88,800,000
Weighted-average amortization period											3 years 10 months 24 days		2 years		1 year 10 months 17 days		3 years 1 month 6 days
Fair value of options vested	8,400,000
Unrecognized expense													300,000
Fair value unvested restricted stock awards (usd per share)													$ 88.33	$ 29.44
Intrinsic value of unvested restricted stock awards													8,400,000
Repurchased shares of common stock (in shares)												29,803
Shares subject to repurchase (in shares)	1,800,000.0	1,800,000.0
Aggregate price of shares subject to repurchase	$ 5,600,000	$ 5,600,000