STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Ordinary Shares IPO		Ordinary Shares Private Placement		Ordinary Shares		Additional paid-in capital IPO	Additional paid-in capital Private Placement	Additional paid-in capital	Accumulated deficit	IPO	Private Placement	Total
Balance, beginning at Dec. 31, 2014					$ 2	[1]			$ 2,007	$ (38,330)			$ (36,321)
Balance, beginning (in shares) at Dec. 31, 2014					502,224
Increase (decrease) in Stockholders' Equity
Exercise of options into Ordinary Shares									145				145
Exercise of options into Ordinary Shares (in shares)					56,366
Conversion of Convertible Preferred Shares into Ordinary Shares upon IPO					$ 18	[1]			47,057				47,075
Conversion of Convertible Preferred Shares into Ordinary Shares upon IPO (in shares)					7,464,320
Conversion of warrants to purchase Convertible Preferred Shares into Ordinary Shares					$ 2	[1]			5,943				5,945
Conversion of warrants to purchase Convertible Preferred Shares into Ordinary Shares (in shares)					697,448
Conversion of warrants to purchase Convertible Preferred Shares into warrants to purchase Ordinary Shares									87				87
Issuance of Ordinary Shares, net of issuance costs	$ 12	[1]					$ 34,684				$ 34,696
Issuance of Ordinary Shares (in shares)	4,700,000
Issuance of Ordinary Shares, net of underwriters' fees of $98									1,308				1,308
Issuance of Ordinary Shares, net of underwriters' fees (in shares)					165,452
Stock-based compensation									583				583
Net loss										(24,971)			(24,971)
Balance, ending at Dec. 31, 2015					$ 34	[1]			91,814	(63,301)			28,547
Balance, ending (in shares) at Dec. 31, 2015					13,585,810
Increase (decrease) in Stockholders' Equity
Issuance of Ordinary Shares, net of issuance costs			$ 17	[1]				$ 10,783				$ 10,800
Issuance of Ordinary Shares (in shares)			6,554,016
Stock-based compensation									833				833
Net loss										(25,869)			(25,869)
Balance, ending at Dec. 31, 2016					$ 51	[1]			$ 103,430	$ (89,170)			$ 14,311
Balance, ending (in shares) at Dec. 31, 2016					20,139,826

[1] Represents an amount lower than $1.