The closing price for entity's stock on the NASDAQ market at end of period.

No definition available.

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- Definition

The discount rate from market value on specific date that participants pay for shares.

+ References

No definition available.

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- Definition

Represents the total fair value of vested stock options.

+ References

No definition available.

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- Definition

Represents the total fair value of nonvested equity stock units granted during the period.

+ References

No definition available.

+ Details

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- Definition

Represents the total fair value of options for granted during the period.

+ References

No definition available.

+ Details

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- Definition

Represents the number of in-the-money stock options exercisable.

+ References

No definition available.

+ Details

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- Definition

Represents the number of in-the-money stock options outstanding.

+ References

No definition available.

+ Details

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ 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.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

+ Details

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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.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

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- Definition

The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3255-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, 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 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

+ Details

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Balance Type:	na
Period Type:	duration

- 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

+ Details

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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.

+ 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

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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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- 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

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Period Type:	duration

- Definition

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

+ References

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- Definition

Number of options outstanding, including both vested and non-vested 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
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

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Equity Incentive Plans and Stock-Based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Apr. 23, 2015
Stock-Based Compensation
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	$ 0.3	$ 0.0
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	0.00%
Minimum [Member]
Stock-Based Compensation
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	0.00%
Maximum [Member]
Stock-Based Compensation
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	150.00%
Stock Compensation Plan [Member]
Stock-Based Compensation
Shares available for issuance	4,753,369		7,305,368
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	35,400,000			4,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures	458,426
Employee Stock Option [Member]
Stock-Based Compensation
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	6,282,068		7,008,833
Entity Closing Stock Price	$ 13.14
Share Based Compensation Arrangement by Share Based Payment Award Options, In The Money Outstanding, Number	5,672,298
Share Based Compensation Arrangement By Share Based Payment Award, Options in the Money Exercisable, Number	3,471,482
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures	458,426	440,000
Share Based Compensation Arrangement by Share Based Payment Award Options, Grants in Period, Total Fair Value	$ 1.9	$ 2.1
Stock-based compensation	0.8	1.2
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 5.6
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	1 year 7 months 17 days
Total fair value of options vested	$ 21.3
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	2.0	3.1
Proceeds from Stock Options Exercised	$ 2.3
Employee Stock [Member]
Stock-Based Compensation
Shares available for issuance	1,451,643
Share Based Compensation Arrangement by Share Based Payment Award Discount from Market Price Specific Date	15.00%
Stock-based compensation	$ 0.5	$ 0.5
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 0.2
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	1 month
Restricted Stock and Stock Units [Member]
Stock-Based Compensation
Granted (in shares)	2,039,808	1,840,184
Stock-based compensation	$ 5.3	$ 3.2
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 56.4
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	2 years 11 months 16 days
Share Based Compensation Arrangement by Share Based Payment Award Equity Instruments Other than Options Nonvested Requisite Service Period	4 years
Share Based Compensation Arrangement by Share Based Payment Award Equity Instruments Other than Options Nonvested Grants in Period Total Fair Value	$ 26.2	22.7
Stock Options with Market Condition [Member] \| Employee Stock Option [Member]
Stock-Based Compensation
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	915,000		1,135,000
Performance Shares [Member] \| Restricted Stock and Stock Units [Member]
Stock-Based Compensation
Stock-based compensation	$ 0.9	$ 0.6
Director [Member] \| Restricted Stock and Stock Units [Member]
Stock-Based Compensation
Share Based Compensation Arrangement by Share Based Payment Award Equity Instruments Other than Options Nonvested Requisite Service Period	1 year