Share based compensation arrangement by share based payment award award vesting percentage.

No definition available.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options conversion ratio upon vesting.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award minimum expiration period .

+ References

No definition available.

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- Definition

Stock Based Compensation (Textual) [Abstract]

+ References

No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ References

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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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.

+ References

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)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ 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).

+ References

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)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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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 (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Stock-Based Compensation - (Details Textual) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
	May 08, 2017	May 15, 2014	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Oct. 26, 2011
Stock-Based Compensation (Textual) [Abstract]
Common Stock (in shares)	6,510,000	6,510,000					4,160,000
Number of additional shares reserved for issuance (in shares)	2,350,000	2,350,000
Stock-based compensation cost			$ 6,909	$ 5,896	$ 5,161
Unrecognized compensation expense			$ 6,221
Expected period of unrecognized compensation expense			3 years 4 months 27 days
Outstanding stock options (in shares)			0	0	87,026	87,026
Options outstanding (in dollars per share)			$ 0.00	$ 0.00	$ 23.75	$ 23.75
Restricted stock units
Stock-Based Compensation (Textual) [Abstract]
Conversion of common stock upon vesting (in shares)			1
Service period for awards			3 years
Restricted stock units \| Board of Directors
Stock-Based Compensation (Textual) [Abstract]
Service period for awards			1 year
Restricted stock units \| Certain executive management \| Minimum
Stock-Based Compensation (Textual) [Abstract]
Service period for awards			3 years
Restricted stock units \| Certain executive management \| Maximum
Stock-Based Compensation (Textual) [Abstract]
Service period for awards			4 years
Performance Restricted Stock Units
Stock-Based Compensation (Textual) [Abstract]
Conversion of common stock upon vesting (in shares)			1
Service period for awards			2 years
Stock appreciation rights
Stock-Based Compensation (Textual) [Abstract]
Percentage of SARs vesting annually			25.00%
Grant expiration period			10 years