Unrecognized cost of unvested share-based compensation awards.

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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

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

General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

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- Definition

For each plan, identification of the award pricing model or other valuation method used in calculating the weighted average fair values disclosed. The model is also used to calculate the compensation expense that is shown within the balance sheet, income statement, and cash flow. Examples of valuation techniques are lattice models (binomial model), closed-form models (Black-Scholes-Merton formula), and a Monte Carlo simulation technique. Fair value is the amount at which an asset or liability could be bought or incurred or sold or settled in a current transaction between willing parties, that is, other than in a forced or liquidation sale. May include disclosures about the assumptions underlying application of the method selected.

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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

Description of pertinent provisions of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

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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

Stock Incentive Plans.

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No definition available.

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Stock Incentive Plans (Details Textuals) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	May 31, 2016
Long Term Incentive Plan [Member]
Stock Incentive Plans (Textuals) [Abstract]
Shared based compensation fair value assumptions method used	Monte Carlo model
Shared based compensation payment award description	Awards vest over two to three years after the end of the performance period with a portion vesting immediately at the end of the performance periods.
Stock Incentive Plan [Member] \| Long Term Incentive Plan [Member]
Stock Incentive Plans (Textuals) [Abstract]
Timing of awards granted	Awards granted after May 5, 2016 are issued out of the 2016 Plan.
Number of common stock authorized for Long-Term Incentive Plan		10,000,000
Employee Stock Option [Member] \| Long Term Incentive Plan [Member]
Stock Incentive Plans (Textuals) [Abstract]
Options expiration period	10 years
Employee Stock Option [Member] \| Maximum [Member]
Stock Incentive Plans (Textuals) [Abstract]
Vesting period	5 years
Employee Stock Option [Member] \| Minimum [Member]
Stock Incentive Plans (Textuals) [Abstract]
Vesting period	3 years
Employee Stock Option [Member] \| Employee Stock Option [Member]
Stock Incentive Plans (Textuals) [Abstract]
Aggregate intrinsic value of options exercised under stock incentive plans	$ 1,346
Restricted Stock [Member] \| Maximum [Member]
Stock Incentive Plans (Textuals) [Abstract]
Vesting period	3 years
Restricted Stock [Member] \| Minimum [Member]
Stock Incentive Plans (Textuals) [Abstract]
Vesting period	2 years
Restricted Stock [Member] \| Stock Option Restricted Stock Deferred Stock Units And Dividend Equivalent Rights [Member]
Stock Incentive Plans (Textuals) [Abstract]
Unrecognized compensation cost related to unvested stock options granted stock under our stock incentive plans	$ 31,709
Expected recognized period	3 years