Adoption of new accounting pronouncement increase in deferred tax assets to record excess tax benefit.

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Adoption of new accounting pronouncement increase in deferred tax assets to record unrecognized excess tax benefits.

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Number of large customers.

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Regulatory milestone payment.

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Summary Of Significant Accounting Policy [Line Items]

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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Amount of direct write-downs of accounts receivable charged against the allowance.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

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Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Amount of consideration paid in advance for advertising that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

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

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Summary of Significant Accounting Policies - Additional Information (Detail)	1 Months Ended	12 Months Ended
	Apr. 30, 2016 USD ($)	Dec. 31, 2019 USD ($) Customer Segment shares	Dec. 31, 2018 USD ($) Customer shares	Dec. 31, 2017 USD ($) Customer shares	Jan. 01, 2018 USD ($)
Summary Of Significant Accounting Policy [Line Items]
Accounts receivable written off		$ 0	$ 100,000
Charge on finished goods inventory		1,100,000	2,700,000	$ 700,000
Impairment losses		0
One-time contingent regulatory milestone payment pursuant to agreement with Ipsen Group	$ 8,000,000.0
Finite-lived intangible assets, net	$ 8,000,000.0
Amortization of intangible assets		1,477,000	1,476,000	1,477,000
Estimated future amortization expense, 2020		1,500,000
Estimated future amortization expense, 2021		1,000,000.0
Advertising costs		38,300,000	39,800,000	$ 15,600,000
Advertising costs capitalized as prepaid expenses		0	0
Revenue recognition		$ (1,704,122,000)	$ (1,468,863,000)
Number of large customers \| Customer		4	4	4
Antidilutive securities to purchase common stock \| shares		19,516,000	20,824,000	18,526,000
Number of business segments \| Segment		1
Tax rate		21.00%	21.00%	35.00%
Customer Concentration Risk \| Revenue, Product and Service Benchmark \| Four Customers
Summary Of Significant Accounting Policy [Line Items]
Concentration risk, percentage		77.00%	85.00%	89.00%
Customer Concentration Risk \| Accounts Receivable \| Four Customers
Summary Of Significant Accounting Policy [Line Items]
Concentration risk, percentage		75.00%	84.00%	87.00%
Topic 606
Summary Of Significant Accounting Policy [Line Items]
Cumulative-effect adjustment to retained earnings					$ 0
Increase to additional paid-in capital with corresponding increase to accumulated deficit					$ 0
Topic 606 \| Difference effect of change - higher (lower)
Summary Of Significant Accounting Policy [Line Items]
Revenue recognition		$ 0
ASU 2016-09
Summary Of Significant Accounting Policy [Line Items]
Cumulative-effect adjustment to retained earnings		300,000
Increase in deferred tax assets to record unrecognized excess tax benefits		36,800,000
Increase to additional paid-in capital with corresponding increase to accumulated deficit		300,000
Increase in deferred tax assets to record excess tax benefit		$ 100,000