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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Stock-Based Compensation (Details 1) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Jul. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	May 31, 2013
Stock-based compensation
Stock-based compensation		$ 2,662	$ 2,673	$ 5,442
Stock Options
Stock-based compensation
Shares outstanding		308,967	370,547	460,213	446,365
Weighted average exercise price of options outstanding		$ 60.80	$ 77.23	$ 87.36	$ 114.99
2013 Plan
Stock-based compensation
Shares authorized						500,000
Shares available for grant		100,000
2013 Plan \| Stock Options
Stock-based compensation
Shares outstanding		0
2013 Plan \| Stock Options \| Minimum
Stock-based compensation
Weighted average exercise price of options outstanding		$ 16.70
2013 Plan \| Stock Options \| Maximum
Stock-based compensation
Weighted average exercise price of options outstanding		$ 88.50
2013 CEO Plan \| Restricted Stock Units
Stock-based compensation
Accelerated compensation cost	$ 1,200
2013 CEO Plan \| Stock Options
Stock-based compensation
Accelerated compensation cost	$ 500
Inducement Awards \| Stock Options
Stock-based compensation
Shares outstanding		100,000
Inducement Awards \| Stock Options \| Minimum
Stock-based compensation
Weighted average exercise price of options outstanding		$ 10.00
Inducement Awards \| Stock Options \| Maximum
Stock-based compensation
Weighted average exercise price of options outstanding		$ 42.60
2005 Plan
Stock-based compensation
Shares available for grant		0
2005 Plan \| Stock Options
Stock-based compensation
Shares outstanding		100,000
2005 Plan \| Stock Options \| Minimum
Stock-based compensation
Weighted average exercise price of options outstanding		$ 60.40
2005 Plan \| Stock Options \| Maximum
Stock-based compensation
Weighted average exercise price of options outstanding		$ 159.00