SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Details)	3 Months Ended	12 Months Ended
Mar. 31, 2020 USD ($) Segment	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)
Significant Accounting Policies [Line Items]
Restricted cash balances as collateral for corporate credit cards	$ 100,000	$ 100,000	$ 100,000
Marketable securities, weighted average remaining maturity	2 months 3 days
Asset impairment charges			$ 19,000,000
Equipment estimated useful life	3 years
Impairment of Long-Lived Assets	$ 0	0
Impairment of goodwill	0	0
Revenues from product sales to date	$ 0
Number of operating segments \| Segment	1
In-Process Research and Development
Significant Accounting Policies [Line Items]
Asset impairment charges	$ 0	$ 0

Marketable securities, weighted average remaining maturity.

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Significant accounting policies.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Amount of cash restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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