Cash, cash equivalents and available-for-sale securities valued at fair value.

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- Definition

Financial assets:

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- Definition

Financial liabilites:

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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No definition available.

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled within one year or the normal operating cycle, if longer.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer.

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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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No definition available.

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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 liability 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
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Fair value of financial and nonfinancial obligations.

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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	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 05, 2018
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements	$ 0	$ (858)	$ 0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	0	41,631
Financial and Nonfinancial Liabilities, Fair Value Disclosure	0	1,071
Financial assets:
Cash, Cash Equivalents and Available-for-Sale Securities, Fair Value	168,982	365,680
Warrants and Rights Outstanding	14,152	62
Royalty rights - at fair value	266,196
Assets, Fair Value	493,879	603,291
Financial liabilites:
Business Combination, Contingent Consideration, Liability, Current	0	1,071		$ 920
Business Combination, Contingent Consideration, Liability, Noncurrent				$ 640
Money Market Funds [Member]
Financial assets:
Cash and Cash Equivalents, Fair Value	131,264	226,719
Equity Securities [Member]
Financial assets:
Available for Sale Securities, Fair Value	82,267	0
Fair Value Level 1 [Member]
Financial assets:
Assets, Fair Value	213,531	226,719
Fair Value Level 1 [Member] \| Money Market Funds [Member]
Financial assets:
Cash and Cash Equivalents, Fair Value	131,264	226,719
Fair Value Level 1 [Member] \| Equity Securities [Member]
Financial assets:
Available for Sale Securities, Fair Value	82,267	0
Fair Value Level 2 [Member]
Financial assets:
Warrants and Rights Outstanding	14,152	62
Assets, Fair Value	14,152	62
Fair Value Level 2 [Member] \| Money Market Funds [Member]
Financial assets:
Cash and Cash Equivalents, Fair Value	0	0
Fair Value Level 2 [Member] \| Equity Securities [Member]
Financial assets:
Available for Sale Securities, Fair Value	0	0
Fair Value Level 3 [Member]
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	0	1,071
Financial assets:
Royalty rights - at fair value	266,196	376,510
Assets, Fair Value	266,196	376,510
Financial liabilites:
Business Combination, Contingent Consideration, Liability, Current	0	1,071
Contingent Consideration [Member]
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value	0	$ (1,071)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements	$ 1,071