Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

No definition available.

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- Definition

Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

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- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

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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.

+ References

No definition available.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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Amount of income tax expense (benefit) from continuing operations attributable to an adjustment of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity.

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Acquisitions - Additional Information (Detail) - USD ($) $ in Thousands			1 Months Ended	3 Months Ended	9 Months Ended
	Apr. 27, 2017	Jan. 06, 2017	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2018
Business Acquisition [Line Items]
Purchase price based on the fair value of outstanding equity	$ 35,846
Impairment charges and corresponding decrease to carrying value					$ 21,692
Mast [Member]
Business Acquisition [Line Items]
Business combination completion date	Apr. 27, 2017
Merger agreement, effective date		Jan. 06, 2017
Purchase price based on the fair value of outstanding equity	$ 35,800
Tax benefit related to reduction in deferred tax liability				$ 4,600
Mast [Member] \| IPR&D [Member]
Business Acquisition [Line Items]
Impairment charges and corresponding decrease to carrying value				21,700	$ 21,700
Tax benefit related to reduction in deferred tax liability				$ 4,600
Cardeas [Member]
Business Acquisition [Line Items]
Common stock upfront payment, shares			107,579
Common stock upfront payment, value			$ 1,000