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.

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Unrecognized cost of unvested share-based compensation awards.

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

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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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The weighted average fair value at grant date for nonvested equity-based awards issued 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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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.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Percentage of vesting of share-based compensation awards.

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Stockholders' Equity - Restricted Stock Units (Details) - Service-Based RSUs - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Number of Shares
Outstanding at the beginning of the period (in shares)	2,279,601
Granted (in shares)	0
Vested (in shares)	(952,032)
Forfeited or expired (in shares)	(95,764)
Outstanding at the end of the period (in shares)	1,231,805	2,279,601
Weighted Average Fair Value at Grant Date
Outstanding at the beginning of the period (in dollars per share)	$ 1.88
Granted (in dollars per share)		$ 1.36	$ 1.36
Vested (in dollars per share)	2.13
Forfeited or expired (in dollars per share)	1.59
Outstanding at the end of the period (in dollars per share)	$ 1.71	$ 1.88
Total unrecognized compensation cost related to non-vested shares	$ 0.8
Weighted average period over which the total unrecognized compensation cost related to non-vested shares is expected to be recognized	10 months 28 days
Stock-based compensation expense	$ 1.5	$ 3.0	$ 5.9
Vesting over the first year
Weighted Average Fair Value at Grant Date
Vesting percentage	34.00%
Vesting over the second year
Weighted Average Fair Value at Grant Date
Vesting percentage	33.00%
Vesting over the third year
Weighted Average Fair Value at Grant Date
Vesting percentage	33.00%