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Common stock shares held by related parties.

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Number of executives.

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Percentage of common stock issued shares.

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Percentage of outstanding common stock holding.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Carrying amount as of the balance sheet date of obligations due all related parties.

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The amount for notes payable (written promise to pay), due to related parties.

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Per share or per unit amount of equity securities issued.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Related Party Transactions - Additional Information (Detail)	3 Months Ended	12 Months Ended
	Mar. 31, 2017 USD ($) RelatedParty	Dec. 31, 2017 USD ($) Executive shares	Dec. 31, 2016 USD ($) shares	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Jun. 14, 2017 shares
Related Party Transaction [Line Items]
Stock-based compensation expense recognized		$ 14,591,000	$ 19,511,000	$ 15,527,000
Percentage of outstanding common stock holding		5.00%	5.00%
Convertible Bonds
Related Party Transaction [Line Items]
Amounts owed to related party	$ 4,000,000	$ 24,000,000	$ 24,000,000
Amount purchased in convertible bonds by holders of outstanding common stock and entity affiliate	$ 2,000,000		10,000,000
Number of related parties received convertible bonds \| RelatedParty	2
Bonds converted into shares of common stock \| shares						2,727,273
Restricted Stock
Related Party Transaction [Line Items]
Stock-based compensation expense recognized		$ 2,160,000	8,534,000	$ 4,035,000
Executive Officer
Related Party Transaction [Line Items]
Issuance of restricted stock \| shares		2,520,000		1,200,000	1,320,000
Promissory notes issued				$ 6,600,000	$ 6,000,000
Stock Price \| $ / shares				$ 5.50	$ 4.55
Promissory note maturity term		3 years
Stock-based compensation expense recognized		$ 0	$ 6,900,000	$ 4,000,000
Number of executives \| Executive		1
Executive Officer \| Restricted Stock
Related Party Transaction [Line Items]
Restricted shares vesting period		3 years
Avalon BioMedical
Related Party Transaction [Line Items]
Common stock shares held by related parties \| shares		678,880	678,880
Percentage of common stock issued shares		1.17%
Pharma Essentia
Related Party Transaction [Line Items]
Licenses revenue		$ 500,000	$ 0	100,000
Taisheng
Related Party Transaction [Line Items]
Purchases of pharmaceutical ingredients from related party		0	200,000	100,000
Amounts owed to related party		0	0
ZenRx
Related Party Transaction [Line Items]
Licenses revenue		0	0	0
Amounts owed to related party		100,000
ZenRx \| Clinical Development Services
Related Party Transaction [Line Items]
Payments to related party for services received		600,000		200,000
ZenRx \| Clinical Development Services \| Maximum
Related Party Transaction [Line Items]
Payments to related party for services received			100,000
RSJ Consulting LLC
Related Party Transaction [Line Items]
Consulting services incurred		$ 100,000	$ 200,000	$ 100,000