Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Significant Accounting Policies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Significant Accounting Policies [Line Items]
Impairment of Long-Lived Assets	$ 0	$ 0
Stock option shares outstanding not included in the calculation of net income per common share			154,057
Account Payable and Accrued Expenses [Member]
Significant Accounting Policies [Line Items]
Liability classified stock options	$ 261	$ 0
Minimum [Member] \| Revenue from Rights Concentration Risk [Member] \| Collaboration Research And Development Revenue [Member]
Significant Accounting Policies [Line Items]
Collaborative Research And Development Revenue	10.00%