Share based compensation arrangement by share based payment award fair value granted.

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- Definition

Share based compensation arrangement by share based payment award fair value vesting period.

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- Definition

Share based compensation arrangement by share based payment award number of installments.

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- Definition

Share-based compensation arrangement by share-based payment award percentage of shares to be increased before vesting period.

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- Definition

Share-based compensation arrangement by share-based payment award, share performance period.

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- Definition

Share-based compensation arrangement by share-based payment award, share price to be increased before vesting period..

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- Definition

Share based compensation arrangement by share based payment granted unit.

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- Definition

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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- Definition

Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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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

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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- 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 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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- 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

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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

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

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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-Topic 718
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-Section 50
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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

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

+ References

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

Price of a single share of a number of saleable stocks of a company.

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No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Weighted average grant-date fair value of options vested.

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No definition available.

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- Definition

Number of share options (or share units) exercised during the current period.

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Equity-Based Compensation - Additional Information (Details) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 30, 2018 USD ($) Executive $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options granted, fair value \| $ / shares		$ 1.91	$ 1.64	$ 0.96
Dividends paid \| $				$ 2,890
Closing price of company's stock granted to senior management \| $ / shares		$ 4.08
Stock-based compensation expense for non-vested equity-based compensation \| $		$ 2,000
Stock based compensation expense, recognition period		13 months
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period		4 years
Dividends paid \| $		$ 0	$ 0
Restricted Stock [Member] \| Stock Vesting, One Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares vesting percentage		25.00%
Restricted Stock [Member] \| Stock Vesting, Two Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares vesting percentage		25.00%
Restricted Stock [Member] \| Stock Vesting, Three Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares vesting percentage		25.00%
Restricted Stock [Member] \| Stock Vesting, Four Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares vesting percentage		25.00%
Performance Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	3 years
Expected volatility		34.50%
Expected dividend yield		0.00%
Risk-free rate of return		2.47%
Number of shares, granted		216,600
Closing price of company's stock granted to senior management \| $ / shares		$ 8.18
Number of shares, canceled		0
Number of shares, outstanding		216,600
Granted units \| Executive	1
Stock option fair value vested \| $	$ 100
Stock option fair value vesting period	3 years
Performance Shares [Member] \| Stock Vesting, One Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period		3 years
Shares vesting percentage		50.00%
Closing price of company's stock granted to senior management \| $ / shares		$ 12.27
Percentage of shares to be increased before vesting period		50.00%
Shares performance period		30 days
Derived services period		1 year 3 months 3 days
Performance Shares [Member] \| Stock Vesting, One Year From Grant Date [Member] \| Binomial Model [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share price to be increased before vesting period \| $ / shares		$ 2.30
Performance Shares [Member] \| Stock Vesting, Two Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period		3 years
Shares vesting percentage		50.00%
Closing price of company's stock granted to senior management \| $ / shares		$ 16.36
Percentage of shares to be increased before vesting period		100.00%
Shares performance period		30 days
Derived services period		1 year 10 months 6 days
Performance Shares [Member] \| Stock Vesting, Two Year From Grant Date [Member] \| Binomial Model [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share price to be increased before vesting period \| $ / shares		$ 1.30
2010 Equity Award Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized		3,750,000
Number of shares available for grant		1,700,000
Stock options granted		13,100	48,500	180,384
Options exercised (in shares)		100,000	0	0
2010 Equity Award Plan [Member] \| Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, granted		483,800	292,342	537,160
Number of shares, canceled		35,393	90,264	188,736
Number of shares, outstanding		850,927	507,036	406,918	77,624
2010 Equity Award Plan [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Years of annual installments in which stock options become exercisable		3 years
Award vesting period		1 year
2010 Equity Award Plan [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Years of annual installments in which stock options become exercisable		4 years
Award vesting period		15 years
2000 Equity Award Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for grant		0
Weighted average remaining contractual life		9 years 6 months
Options exercised (in shares)		286,875	232,750	182,500
Intrinsic value of shares exercised \| $		$ 1,100	$ 300	$ 300
2000 Equity Award Plan [Member] \| Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, outstanding		40,000	40,000	61,500	141,500
2000 Equity Award Plan [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Years of annual installments in which stock options become exercisable		3 years
Award vesting period		1 year
2000 Equity Award Plan [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Years of annual installments in which stock options become exercisable		4 years
Expiration period		15 years
1991 Equity Award Plan [Member] \| Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized		800,000
Number of shares available for grant		7,000
Number of shares, granted			57,900	16,371
Number of shares, canceled		2,400	18,975	55,275
Number of shares, outstanding		56,117	90,454	84,352	189,525
2010 Equity Award Plan [Member] \| Employee Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options granted	13,100	0
Stock options granted, fair value \| $ / shares	$ 1.91
Stock option vest, fair value \| $ / shares	$ 6.45
Expected term	3 years 8 months 12 days
Expected volatility	34.90%
Expected dividend yield	0.00%
Risk-free rate of return	2.40%