Business acquisition contingent consideration potential cash payments upon achievement of sales milestone.

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- Definition

Collaborative Arrangement, Minority Equity Investment in License

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Common stock shares held

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Milestone payments received.

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Receivable from sale of Assets, contingent upon successful development and commercialization.

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Royalties receivable percentage of net sales.

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Royalty rate lower limit.

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Royalty rate upper limit.

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Termination of collaborative agreement.

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Amount of 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. Excludes cash and cash equivalents within disposal group and discontinued operation.

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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 obligation to transfer good or service to customer for which consideration has been received or is receivable.

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The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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Amount of gain (loss) on sale or disposal of intangible assets.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The cash outflow to acquire an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among myriad other features and characteristics.

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The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets.

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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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Collaboration and License Agreements - Additional Information (Detail) $ in Thousands, € in Millions		1 Months Ended		3 Months Ended	12 Months Ended
	Oct. 06, 2015 USD ($)	Oct. 31, 2019 USD ($)	Jul. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2019 EUR (€) shares	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) shares	Dec. 31, 2017 USD ($)	Dec. 31, 2013 USD ($) shares	Dec. 31, 2019 USD ($) shares	Mar. 31, 2019	Sep. 30, 2017 USD ($)
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Net product revenues						$ 1,704,048	$ 1,491,212	$ 1,313,646
Contract liability										$ 8,800
Net gain on sale of intangible assets						$ 25,000	50,000	125,000
Termination of collaborative agreement prior to written notice in number of days					90 days	90 days
Firdapse \| Disposal Group, Disposed of by Sale, Not Discontinued Operations
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Royalties on net product sales											7.00%
Royalties on net product sales											10.00%
Talazoparib
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Net gain on sale of intangible assets				$ 369,500
Medivation
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront payment received	$ 410,000
Milestone payments												$ 160,000
Milestone Payments Received						$ 25,000	$ 50,000
Merck Serono
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Business acquisition, cash paid						374,500
Licensing Agreement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Carrying value										$ 5,000
A&R Kuvan Agreement \| Merck Serono \| Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Business acquisition contingent consideration potential cash payments upon achievement of sales milestone \| €					€ 60.0
Pegvaliase Agreement \| Merck Serono
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Business acquisition, cash paid \| €					125.0
Pegvaliase Agreement \| Merck Serono \| Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Business acquisition contingent consideration potential cash payments upon achievement of sales milestone \| €					€ 67.3
Catalyst Pharmaceutical Partners, Inc.
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Licensing arrangement, convertible promissory note received									$ 5,000
Licensing arrangement, shares received upon conversion promissory note \| shares									6,700,000
Common stock shares held \| shares					0		0			0
Exclusive Licensing Agreement For Tralesinidase Alfa
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Net product revenues		$ 3,000
Investment in equity		$ 5,000
United States
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Net product revenues						$ 778,440	$ 696,793	$ 588,243
Sarepta Therapeutics \| License Agreement And Settlement Agreement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Net product revenues			$ 31,500
Sarepta Therapeutics \| United States \| License Agreement And Settlement Agreement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Royalties receivable percentage of net sales			5.00%
Sarepta Therapeutics \| EU and Other Countries \| License Agreement And Settlement Agreement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Royalties receivable percentage of net sales			8.00%