CONSOLIDATED UNAUDITED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Parenthetical) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Warrant [Member]
Pre-funded warrants to purchase ordinary shares	1,024,876	450,909
Pre-funded warrants to purchase price	$ 2.57	$ 5.49
Registered Direct Public Offering [Member]
Issuance expenses	$ 987	$ 2,381

Amount of decrease in additional paid in capital (APIC) resulting from direct costs associated with issuing stock. Includes, but is not limited to, legal and accounting fees and direct costs associated with stock issues under a shelf registration.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration