Financial assets:

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- Definition

Royalty rights

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Value of the investment at close of period. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

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- Definition

Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

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Fair Value Measurements (Financial Instruments Measured at Fair Value on a Recurring Basis) (Detail) - USD ($) $ in Thousands	8 Months Ended
	Aug. 31, 2020	Dec. 31, 2019
Financial assets:
Assets, Fair Value		$ 493,879
Warrants and Rights Outstanding		14,152
Equity Securities [Member]
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in and Advances to Affiliates, at Fair Value		82,267
Money Market Funds [Member]
Financial assets:
Cash and Cash Equivalents, Fair Value		131,264
Fair Value Level 1 [Member]
Financial assets:
Assets, Fair Value		213,531
Fair Value Level 1 [Member] \| Equity Securities [Member]
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in and Advances to Affiliates, at Fair Value		82,267
Fair Value Level 1 [Member] \| Money Market Funds [Member]
Financial assets:
Cash and Cash Equivalents, Fair Value		131,264
Fair Value Level 2 [Member]
Financial assets:
Assets, Fair Value		14,152
Warrants and Rights Outstanding		14,152
Fair Value Level 2 [Member] \| Equity Securities [Member]
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in and Advances to Affiliates, at Fair Value		0
Fair Value Level 2 [Member] \| Money Market Funds [Member]
Financial assets:
Cash and Cash Equivalents, Fair Value		0
Fair Value Level 3 [Member]
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Royalty rights		266,196
Financial assets:
Assets, Fair Value		$ 266,196
Royalty right [Member]
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	$ (43,933)
VB [Member] \| Royalty right [Member]
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	$ (9,408)