CONDENSED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands		Total	Ordinary Share	Additional paid-in capital	Accumulated deficit	ATM Offering Program	ATM Offering Program Ordinary Share	ATM Offering Program Additional paid-in capital	Follow On Public Offering	Follow On Public Offering Ordinary Share	Follow On Public Offering Additional paid-in capital
Balance at Dec. 31, 2015		$ 20,920	$ 33	$ 94,876	$ (73,989)
Balance (in shares) at Dec. 31, 2015			12,222,583
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation to employees and non-employees		3,398		3,398
Issuance of ordinary shares upon exercise of options to purchase ordinary shares and RSUs by employees and non-employees		18	$ 1	17
Issuance of ordinary shares upon exercise of options to purchase ordinary shares and RSUs by employee and non employees (in shares)			128,496
Issuance of ordinary shares in an offering, net of issuance expenses						$ 4,099	$ 2	$ 4,097	$ 11,089	$ 9	$ 11,080
Issuance of ordinary shares in an offering, net of issuance expenses (in shares)							692,062			3,250,000
Issuance of warrants to purchase ordinary shares		1,239		1,239
Cashless exercise of warrants into ordinary shares			45,116
Net loss		(32,503)			(32,503)
Balance at Dec. 31, 2016		8,260	$ 45	114,707	(106,492)
Balance (in shares) at Dec. 31, 2016			16,338,257
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect to stock based compensation from adoption of a new accounting standard		0		11	(11)
Share-based compensation to employees and non-employees		851		851
Issuance of ordinary shares upon exercise of options to purchase ordinary shares and RSUs by employees and non-employees		$ 20		20
Issuance of ordinary shares upon exercise of options to purchase ordinary shares and RSUs by employee and non employees (in shares)		22,475	26,807
Issuance of ordinary shares in an offering, net of issuance expenses	[1]					$ 611	$ 1	$ 610
Issuance of ordinary shares in an offering, net of issuance expenses (in shares)	[1]						307,467
Net loss		$ (6,400)			(6,400)
Balance at Mar. 31, 2017		$ 3,342	$ 46	$ 116,199	$ (112,903)
Balance (in shares) at Mar. 31, 2017			16,672,531

[1] See Note 7e to the condensed consolidated financial statements.