Share Based Compensation Arrangement by Share Based Payment Award, Options, Expiration Term

No definition available.

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- Definition

Share-based Compensation Arrangement By Share-based Payment Award, Fair Value Assumptions, Period Used To Determine Volatility

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No definition available.

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- Definition

Stock Repurchase Program, Increase To Authorized Amount

+ References

No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

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No definition available.

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- Definition

Face amount or stated value per share of common stock.

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

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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.

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- References

No definition available.

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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

+ References

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- Definition

The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ References

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- Definition

Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

+ References

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- Definition

Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

+ 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

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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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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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

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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

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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 50
-Paragraph 2
-Subparagraph (f)(2)(i)
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-Name Accounting Standards Codification
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- Definition

Value of stock issued as a result of the exercise of stock options.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Name Accounting Standards Codification
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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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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

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-Topic 210
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Stockholders' Equity (Narrative) (Details) - USD ($)				3 Months Ended
Stockholders' Equity (Narrative) (Details) - USD ($)	Apr. 25, 2018	Apr. 30, 2017	Jun. 07, 2012	Mar. 31, 2018	Mar. 31, 2017	Jan. 31, 2018	Dec. 31, 2017	Nov. 21, 2016	Feb. 16, 2016	Jul. 23, 2014	Mar. 13, 2014	Dec. 10, 2012	Jun. 30, 2010
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Common stock, shares authorized (in shares)				100,000,000			100,000,000
Common stock, shares issued (in shares)				60,537,707			59,663,969
Common stock, shares outstanding (in shares)				60,537,707			59,663,969
Common stock, par value (in dollars per share)				$ 0.001			$ 0.001
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Preferred stock, shares authorized (in shares)				5,000,000			5,000,000
Preferred stock, shares issued (in shares)				0			0
Preferred stock, shares outstanding (in shares)				0			0
Preferred stock, par value (in dollars per share)				$ 0.001			$ 0.001
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchased during period (in shares)				93,750
Stock repurchase program, remaining authorized repurchase amount				$ 17,100,000
Per share weighed average fair value of stock options granted during the period (in dollars per share)				$ 5.74	$ 2.92
Dividend yield				0.00%	0.00%
Expected life				5 years	5 years
Period used to determine volatility				5 years
Total value of stock options exercised				$ 3,300,000
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to nonvested share-based compensation arrangements				$ 15,600,000
Weighted average recognition period of unrecognized compensation cost				3 years
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to nonvested share-based compensation arrangements				$ 17,100,000
Weighted average recognition period of unrecognized compensation cost				2 years 7 months 6 days
Vesting period				4 years
1998 Plan [Member] \| Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock available for issuance (up to)				5,850,000
2000 Plan [Member] \| Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in number of shares of common stock available for issuance				4,150,000
1998 and 2000 Plan [Member] \| Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock available for issuance (up to)				10,000,000
2009 Plan [Member] \| Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock available for issuance (up to)				3,900,000
Increase in number of shares of common stock available for issuance		4,000,000		6,000,000
Stock option term				10 years
2010 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock available for issuance (up to)		2,000,000		1,000,000									1,000,000
Increase in number of shares of common stock available for issuance		1,000,000
2018 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock available for issuance (up to)						1,500,000
2018 Plan [Member] \| Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for future issuance				300,000
2009 Plan [Member] \| 2009 Plan [Member] \| Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock available for issuance (up to)		27,817,744
Increase in number of shares of common stock available for issuance			4,250,000
2012 Stock Repurchase Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchase program, authorized amount								$ 74,000,000.0	$ 64,000,000.0	$ 50,000,000.0	$ 40,000,000.0	$ 30,000,000.0
Increase to authorized amount									$ 14,000,000
Subsequent Event [Member] \| 2018 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock available for issuance (up to)	2,000,000
Increase in number of shares of common stock available for issuance	500,000