Summary of Significant Accounting Policies Narrative (Details) (USD $) Share data in Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014 Segment	Dec. 31, 2013
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Restricted cash pledged as collateral	$ 37,000	$ 37,000
Property and equipment	279,000us-gaap_PropertyPlantAndEquipmentGross	38,000us-gaap_PropertyPlantAndEquipmentGross
Depreciation expense	17,000us-gaap_Depreciation	5,000us-gaap_Depreciation
Potentially dilutive securities excluded from calculation of diluted net loss per share	13.1	8.2
Comprehensive income	21,300,000	17,900,000
Number of segments	1us-gaap_NumberOfOperatingSegments
Clinical Trials [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Prepaid expenses	$ 1,528,000

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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Carrying amount as of the balance sheet date of cash collateral held for borrowed securities, for which the cash is restricted as to withdrawal or usage.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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