Employee Stock Purchase Plan, Weighted-Average Price Per Share

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- Definition

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

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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.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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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.

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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).

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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.

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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.

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- Definition

Number of additional shares authorized for issuance under share-based payment arrangement.

+ References

No definition available.

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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

Percentage of vesting of award under share-based payment arrangement.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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Equity Incentive Plans and Stock-Based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Stock-based compensation
Employee stock purchase plan, shares issued during period			277,838	429,396
Employee stock purchase plan, weighted-average price per share			$ 10.51	$ 7.95
Fair Value Assumptions, Expected Dividend Rate (as a percentage)			0.00%
Options
Stock-based compensation
Stock-based compensation expense	$ 0.1	$ 0.2	$ 0.3	$ 0.5
Unrecognized compensation cost	$ 1.5		$ 1.5
Unrecognized compensation cost, weighted-average period			2 years
Employee stock purchase plan
Stock-based compensation
Number of additional shares authorized			2,000,000
Shares available for issuance	3,400,000		3,400,000
Discount from market price specific date			15.00%
Stock-based compensation expense	$ 0.2	0.3	$ 0.7	0.8
Unrecognized compensation cost	0.5		$ 0.5
Unrecognized compensation cost, weighted-average period			4 months
Nonvested equity stock units and stock units
Stock-based compensation
Stock-based compensation expense	6.3	$ 6.5	$ 11.8	$ 12.9
Unrecognized compensation cost	$ 45.1		$ 45.1
Unrecognized compensation cost, weighted-average period			2 years 6 months
Awards, nonvested grants in period, shares	100,000	300,000	1,872,547	3,700,000
Awards, nonvested grants in period, fair value	$ 1.7	$ 3.4	$ 29.3	$ 35.6
Awards, nonvested requisite service period			4 years
Nonvested equity stock units and stock units \| Director
Stock-based compensation
Awards, nonvested requisite service period			1 year
Nonvested equity stock units and stock units \| Minimum
Stock-based compensation
Awards, vesting rights (as a percentage)			0.00%
Nonvested equity stock units and stock units \| Maximum
Stock-based compensation
Awards, vesting rights (as a percentage)			200.00%