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- Definition

Percentage of shares vested in lieu of directors fees at the grant date.

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Portion of director fees matched to deferred stock units.

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- Definition

Share based compensation arrangement by share based payment award expiration term.

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- Definition

Share based compensation arrangement by share based payment deferred award vesting period.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Number of Award Vesting Types

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No definition available.

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- Definition

The amount of expense, net of income tax, 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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- Definition

Aggregate number of common shares reserved for future issuance.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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.

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-Topic 718
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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.

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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

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-Publisher FASB
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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.

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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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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).

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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.

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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- Definition

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

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No definition available.

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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.

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- Definition

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

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- Definition

Number of non-vested options outstanding.

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No definition available.

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- Definition

Number of options vested.

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No definition available.

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Stock-Based Compensation - Additional Information (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($) vesting_type $ / shares shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2016 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved shares of common stock for possible future issuance	3,200,000
Number of award vesting types \| vesting_type	2
Weighted-average grant date fair value of options issued (in dollars per share) \| $ / shares	$ 2.36
Total intrinsic value of options exercised \| $		$ 0.1
Cash liability for performance-based units \| $	$ 0.0
Employee stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options issued (in shares)	0
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	0	0	0
Options vested (in shares)	1,000		1,000
Options forfeited in period (in shares)	76,000		8,000
Stock-based compensation expense \| $	$ (0.7)	$ (0.2)
Options, nonvested, number of shares (in shares)	258,000
Service Based Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	0		8,000
Options forfeited in period (in shares)	17,000		80,000
Stock-based compensation expense \| $	$ 0.0		$ 0.1
Vesting period (in years)	4 years
Expiration term (in years)	8 years
Market Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	0
Stock-based compensation expense \| $		$ 0.0	$ 0.0
Performance Stock Unit [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested (in shares)		1,000
Forfeited (in shares)	117,000	6,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options issued (in shares)	48,000		163,000
Forfeited (in shares)	44,000		3,000
Restricted Stock [Member] \| Non Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options issued (in shares)			22,000
Stock-based compensation expense \| $		$ 0.3
Deferred Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options issued (in shares)	6,000		54,000
Percentage of shares vested in lieu of directors fees at the grant date	100.00%
Portion of Director fees matched to deferred stock units	25.00%
Vesting period of deferred stock (in years)	1 year
Restricted Stock Unit And Performance Stock Unit And Deferred Stock Unit [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense \| $	$ 1.0	$ 1.3
Vested (in shares)	121,000	135,000
Forfeited (in shares)	161,000	10,000
Compensation cost not yet recognized \| $	$ 2.4
Total fair value of stock-based compensation vested \| $	$ 1.6		$ 1.6
2014 Equity Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance	4,100,000
Minimum [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	2 years
Maximum [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	4 years