Accrued liability for ESPP plan employee contributions for shares not yet purchased.

No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights exercised

+ References

No definition available.

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- Definition

Number of warrants or rights exercised.

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No definition available.

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- Definition

Employee Stock Purchase Plan Shares Available For Issuance

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No definition available.

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- Definition

Maximum annual eligible employee contribution amount to Employee Stock Purchase Plan

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No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Cancelled

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No definition available.

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- Definition

Percentage of the company's stock that must be acquired in order to for stock purchase rights to become exercisable.

+ References

No definition available.

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- Definition

Expiration date of outstanding warrants

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No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

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- Definition

Number of warrants or rights outstanding.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(i))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph i

-Article 4

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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)

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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)

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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

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

Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

+ 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

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

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

+ References

+ Details

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- Definition

Intrinsic value of equity-based compensation awards vested. Excludes stock and unit options.

+ References

No definition available.

+ Details

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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 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.

+ 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

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- Definition

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

+ 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)(2)

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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

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

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ 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 (f)(2)(iii)

-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.

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- Definition

Number of share instruments newly issued under a share-based compensation plan.

+ References

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Stockholders' Equity - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 04, 2006
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum percentage before exercise				20.00%
Total fair value of restricted stock units vested	$ 7,000,000	$ 11,800,000	$ 6,200,000
Total fair market value of performance share awards that are vested during the period			4,700,000
Employees share purchase plan, fair market value of common stock at beginning of offering period		85.00%
Employees share purchase plan, fair market value of common stock at end of purchase period		85.00%
Eligible employee contributions		25,000
Shares reserved for issuance	34,696
Shares issued in period	90,067
Employee withholdings for ESPP shares	1,500,000
Expected dividend yield	0.00%
Unrecognized stock-based compensation expense	77,800,000
Unrecognized stock-based compensation expense, weighted-average period for recognition	2 years 4 months 2 days
Warrants to purchase aggregate shares of common stock, Exercised	25,808
Common stock, Exercise price per share	$ 0.78
Warrants to purchase aggregate shares of common stock, Outstanding	20,000
Common stock, Exercise price per share, Outstanding	$ 6.93
Warrants expiration date	2017
Upside Case Achievement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance shares eligible to be earned			83,332
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payments award, expiration term	10 years
Share-based payment awards, vesting period	4 years
Restricted stock units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance shares eligible to be earned	134,865
Performance share awards outstanding	483,580	311,347
Stock appreciation rights granted	399,102
Performance shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share awards outstanding	0	0
Performance shares [Member] \| Upside Case Achievement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share awards canceled during period			41,668
Stock appreciation rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of restricted stock units vested	6,834,000	9,955,000	4,307,000
Total fair market value of performance share awards that are vested during the period	$ 37,900,000
Stock appreciation rights granted	0	0
Stock options and stock appreciation rights to employees and directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock appreciation rights granted	0	0
Expected dividend yield	0.00%	0.00%	0.00%
Annual non-employee directors grants [Member] \| Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment awards, vesting period	1 year
Annual non-employee directors grants [Member] \| Restricted stock units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment awards, vesting period, descriptions	Restricted stock units generally vest in three equal installments on approximately the first, second and third anniversaries of the grant date, except for annual restricted stock unit grants to non-employee directors, which vest on approximately the first anniversary of the grant date.
Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance	21,150,000
Number of shares available for issuance	2,700,000
ESPP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance	3,000,000
Expected dividend yield	0.00%	0.00%
Employee stock purchase plan offerings			0