Allowance for Doubtful Accounts Receivable, Reimbursable Expense, Collaborative Arrangement

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Description of business and significant accounting policies.

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Other Comprehensive Income (Loss), Foreign Currency Transaction And Translation Adjustment, Intercompany Balance, Net Of Tax

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Value Added Tax Potential Payment

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

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- Definition

Face amount or stated value per share of common stock.

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

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Amount of an intercompany foreign currency transactions that is of a long-term-investment nature, that is, settlement is not planned of anticipated in the foreseeable future.

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No definition available.

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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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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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Cash received on stock transaction after deduction of issuance costs.

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Carrying amount as of the balance sheet date of value added taxes due either from customers arising from sales on credit terms, or as previously overpaid to tax authorities.

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Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail) $ / shares in Units, € in Millions	1 Months Ended	12 Months Ended
	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2019 EUR (€)	Dec. 31, 2019 USD ($) $ / shares	Jan. 01, 2019 USD ($)	Dec. 31, 2018 EUR (€)	Dec. 31, 2018 USD ($) $ / shares	Jan. 24, 2018 $ / shares	Jan. 23, 2018 $ / shares
Description Of Business And Significant Accounting Policies [Line Items]
Preferred stock par value (in USD per share) \| $ / shares									$ 0.001	$ 0
Common stock par value (in USD per share) \| $ / shares					$ 0.001			$ 0.001	$ 0.001	$ 0
Accumulated deficit					$ (2,263,563,000)	$ (2,223,550,000)		$ (2,224,746,000)
Available cash and cash equivalents					33,700,000
Allowance for doubtful accounts from collaborative arrangements					0			0
Italian VAT receivables					4,400,000			4,500,000
VAT potential payment				€ 4.3	4,800,000
Foreign currency translation		$ 957,000	$ (1,513,000)
Finance lease					$ 0
Capital lease								0
Leasehold Improvements
Description Of Business And Significant Accounting Policies [Line Items]
Property and equipment useful life		10 years
Minimum \| Assets Other Than Leasehold Improvements
Description Of Business And Significant Accounting Policies [Line Items]
Property and equipment useful life		3 years
Maximum \| Assets Other Than Leasehold Improvements
Description Of Business And Significant Accounting Policies [Line Items]
Property and equipment useful life		5 years
CTI Life Sciences Limited
Description Of Business And Significant Accounting Policies [Line Items]
Foreign currency translation		$ 1,300,000	$ (1,500,000)
Intercompany foreign currency balance receivable							€ 28.7	$ 32,800,000
Aequus Biopharma, Inc
Description Of Business And Significant Accounting Policies [Line Items]
Interest in majority-owned subsidiary				59.70%	59.70%
Aequus Biopharma, Inc \| Affiliated Entity
Description Of Business And Significant Accounting Policies [Line Items]
Interest in majority-owned subsidiary				60.00%	60.00%
Rights Offering \| Subsequent Event
Description Of Business And Significant Accounting Policies [Line Items]
Proceeds from sale of stock	$ 59,300,000