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Contract with Customer, Liability, Customer Deposit, Current

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Payment of sublicense fees.

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- Definition

Significant Accounting Policies [Line Items]

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- Definition

Warrant Liability

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Amount of increase (decrease) to net income used for calculating diluted earnings per share (EPS), resulting from the assumed exercise stock options, restrictive stock units (RSUs), convertible preferred stock of an employee stock ownership plan (ESOP), and other dilutive convertible securities.

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The net amount (to the extent disclosed within this portion of the income statement) by which an insurance settlement exceeds incremental costs incurred from the event causing an interruption of business, plus the insurance award for earnings lost from the event, such as a natural catastrophe, explosion or fire.

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Amount recognized for uncertainty in income taxes classified as current.

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- Definition

The amount of cash paid for royalties during the current period.

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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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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unbilled amounts due for services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

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Accounting Policies - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Mar. 31, 2019	Jan. 01, 2018	Jan. 01, 2017
Significant Accounting Policies [Line Items]
Revenue recognized related to the advance from Healios	$ 0
Cumulative effect of accounting change						$ 1,871,000	$ (110,000)
Accrued capital expenditures		$ 100,000
Payments for royalties	0	0	$ 0
Sublicense fees	100,000	600,000
Gain from insurance proceeds, net	0	617,000	0	$ 700,000
Warrant liabilities	$ 0	0
Contractual term	10 years
Liability for uncertain income tax	$ 0	0
Dilutive effects from warrant liabilities	$ 0	0	$ 0
Healios
Significant Accounting Policies [Line Items]
Unbilled accounts receivable from Healios		3,600,000
Deposit from Healios		$ 2,000,000
Minimum
Significant Accounting Policies [Line Items]
Estimated useful life of long-lived assets	3 years
Annual stock-based awards vesting period		3 years
Maximum
Significant Accounting Policies [Line Items]
Estimated useful life of long-lived assets	10 years
Annual stock-based awards vesting period	4 years
License \| Healios
Significant Accounting Policies [Line Items]
Unbilled accounts receivable from Healios					$ 2,500,000
Retained Earnings
Significant Accounting Policies [Line Items]
Cumulative effect of accounting change						1,871,000	$ (110,000)
Retained Earnings \| ASU 2014-09
Significant Accounting Policies [Line Items]
Cumulative effect of accounting change						$ 1,900,000