Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities:
Net loss	$ (111,581)	$ (80,682)	$ (77,370)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	3,153	1,962	1,216
Asset write-downs and impairment	46	23	19
Accrued interest expense	672		6,070
Share-based compensation to employees	11,860	4,624	5,120
Amortization of discount (premium)	329	(19)	5,432
Increase in receivables and prepaid expenses	(5,088)	(1,192)	(3,611)
Decrease (increase) in inventories	(10,148)	(1,554)	1,479
Increase in other long-term assets	(381)	(44)	(44)
Increase (decrease) in trade payables	6,961	(492)	5,695
Increase in other payables and accrued expenses	3,579	2,324	2,955
Increase in employee benefit liabilities, net	133	42	20
Increase in other long-term liabilities	581	764	302
Net cash used in operating activities	(99,884)	(74,244)	(52,717)
Cash flows from investing activities:
Purchase of property and equipment	(4,667)	(849)	(2,201)
Purchase of field equipment	(5,604)	(1,470)	(1,426)
Decrease (increase) in restricted cash	(26)	1,117	(1,019)
Proceeds from maturity of short-term investments	104,000	93,000	15,048
Purchase of short-term investments	(208,998)	(137,980)
Net cash provided by (used in) investing activities	(115,295)	(46,182)	10,402
Cash flows from financing activities:
Proceeds from issuance of shares, net	252,133		191,738
Proceeds from long-term loan, net	22,886		49,432
Repayment of long-term loans			(58,047)
Proceeds from issuance of other long-term loans		54	193
Repayment of other long-term loans	(63)	(63)
Exercise of options and warrants	2,038	2,154	2
Purchase of shares in respect of settlement	(5)
Net cash provided by financing activities	276,989	2,145	183,318
Increase (decrease) in cash and cash equivalents	61,810	(118,281)	141,003
Cash and cash equivalents at the beginning of the year	57,613	175,894	34,891
Cash and cash equivalents at the end of the year	119,423	57,613	175,894
Cash paid during the year for:
Income taxes	1,489	282	689
Interest	$ 1,688	25	7,131
Non-cash investing and financing activities:
Purchase of property and equipment		$ 239	$ 585