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Period following the issuance date, the warrants become exercisable, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Exercise price per share or per unit of warrants or rights outstanding.

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Face amount or stated value per share of common stock.

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Carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Convertible Notes Payable, excluding current portion. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.

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Contractual interest rate for funds borrowed, under the debt agreement.

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SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($) $ / shares in Units, $ in Millions					1 Months Ended				3 Months Ended		9 Months Ended
	Oct. 01, 2020	Sep. 14, 2020	Mar. 18, 2020	Dec. 19, 2019	Oct. 31, 2020	Jul. 23, 2018	Oct. 19, 2017	Oct. 31, 2015	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Significant Accounting Policies [Line Items]
Common Stock, Par or Stated Value Per Share									$ 0.001	$ 0.001	$ 0.001	$ 0.001
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount									26,905,842	7,854,729	21,405,733	7,826,946
Net proceeds from private placement			$ 41.3
Subsequent Event [Member]
Significant Accounting Policies [Line Items]
Total proceeds from accounts receivable outstanding					$ 2.7
Private Placement [Member]
Significant Accounting Policies [Line Items]
Common Stock, Par or Stated Value Per Share			$ 0.001
Number of shares issued (in shares)		200,000	17,604,423
Purchase price (in dollars per share)			$ 2.485
Number of warrants issued (in shares)			17,604,423
Exercise price of warrants (in dollars per share)			$ 2.36
Exercise of warrants, commencement period			6 months
Term of warrants			5 years
Reverse stock split ratio				one-for-ten
2021 Notes [Member]
Significant Accounting Policies [Line Items]
Convertible Notes Payable, Noncurrent									$ 57.9		$ 57.9
Interest rate (as a percent)									7.50%		7.50%
Debt Instrument, Interest Rate, Stated Percentage									7.50%		7.50%
Seven Point Five Percentage Convertible Notes [Member]
Significant Accounting Policies [Line Items]
Interest rate (as a percent)									7.50%		7.50%
Debt Instrument, Interest Rate, Stated Percentage									7.50%		7.50%
Amended Pfizer Agreement [Member] \| Subsequent Event [Member]
Significant Accounting Policies [Line Items]
Total proceeds from accounts receivable outstanding					1.8
Amended Pfizer Agreement [Member] \| Protalix Bio Therapeutics Incorporation [Member] \| Brazil [Member]
Significant Accounting Policies [Line Items]
Collaborative Arrangement Revenues and Expenses Sharing Percentage								100.00%
ATM Equity Offering Sales Agreement [Member]
Significant Accounting Policies [Line Items]
Number of shares issued (in shares)	30,000,000
ATM Equity Offering Sales Agreement [Member] \| Subsequent Event [Member]
Significant Accounting Policies [Line Items]
Sale of stock, maximum offering price	$ 30.0
Chiesi Agreements [Member] \| Subsequent Event [Member]
Significant Accounting Policies [Line Items]
Total proceeds from accounts receivable outstanding					$ 0.9
Chiesi US Agreement [Member]
Significant Accounting Policies [Line Items]
Upfront Nonrefundable Non-Creditable Payment Receivable						$ 25.0
Additional Amounts Payable To Cover Development Costs						20.0
Maximum Entitlement Of Development Costs To Cover Per Year						7.5
Additional Amount Payable For Achievement Of Regulatory And Commercial Milestones						$ 760.0
Chiesi US Agreement [Member] \| Minimum [Member]
Significant Accounting Policies [Line Items]
Payment On Net Sales Percentage						15.00%
Chiesi US Agreement [Member] \| Maximum [Member]
Significant Accounting Policies [Line Items]
Payment On Net Sales Percentage						40.00%
Chiesi Ex US Agreement [Member]
Significant Accounting Policies [Line Items]
Upfront Nonrefundable Non-Creditable Payment Receivable							$ 25.0
Additional Amounts Payable To Cover Development Costs							25.0
Maximum Entitlement Of Development Costs To Cover Per Year							10.0
Additional Amount Payable For Achievement Of Regulatory And Commercial Milestones							$ 320.0
Chiesi Ex US Agreement [Member] \| Minimum [Member]
Significant Accounting Policies [Line Items]
Payment On Net Sales Percentage							15.00%
Chiesi Ex US Agreement [Member] \| Maximum [Member]
Significant Accounting Policies [Line Items]
Payment On Net Sales Percentage							35.00%