Maximum value of common stock offered for sale under the sales agreement.

No definition available.

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- Definition

The percent of commission paid for gross proceeds of the sale price of all shares sold under the sales agreement.

+ References

No definition available.

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- Definition

Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

+ References

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- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

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-SubTopic 10
-Section 45
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- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

+ References

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-Name Accounting Standards Codification
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- Definition

Number of new stock issued during the period.

+ References

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- Details

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Note 1 - Organization and Operations (Details Textual) - USD ($) $ in Thousands		3 Months Ended
	Nov. 12, 2015	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Cash, Cash Equivalents, and Short-term Investments		$ 34,100
Retained Earnings (Accumulated Deficit)		(166,275)		$ (159,777)
Proceeds from Issuance of Common Stock		$ 105
Sales Agreement [Member] \| Cowen and Company, LLC [Member]
Sale of Stock, Maximum Value of Stock Offered	$ 40,000
Sales of Stock, Commission Paid		3.00%
Stock Issued During Period, Shares, New Issues		93,512
Proceeds from Issuance of Common Stock		$ 200
Payments of Stock Issuance Costs		$ 100