Business acquisition, estimated fair value of free shares.

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- Definition

Business acquisition exchange rate on purchase price.

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Business acquisition, number of free shares held by the holders.

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Business acquisition, number of shares acquired.

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Business acquisition number of shares owned by sellers under block transaction.

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Business acquisition number of vested free shares.

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- Definition

Business acquisition, percentage of equity interests agreed to acquire.

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Business acquisition remaining number of shares owned by seller under block transaction.

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No definition available.

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Business combination, fair value percentage at acquirer recognizes and consolidated assets, liabilities assumed and noncontrolling interests.

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No definition available.

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- Definition

Business combination, loan adjusted in purchase consideration.

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- Definition

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

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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

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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No definition available.

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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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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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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- Definition

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

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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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Acquisition of Txcell S.A. - Additional Information (Detail)		3 Months Ended								12 Months Ended
	Oct. 01, 2018 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2018 € / shares	Oct. 01, 2018 € / shares	Jul. 20, 2018
Business Acquisition [Line Items]
Number of free shares held by the holders \| shares	477,000,000
Business Acquisition Number Of Vested Free Shares \| shares	453,000,000
Revenues		$ 26,837,000	$ 23,562,000	$ 21,416,000	$ 12,637,000	$ 13,077,000	$ 11,812,000	$ 8,253,000	$ 3,425,000	$ 84,452,000	$ 36,567,000	$ 19,389,000
Operating expenses		47,609,000	$ 39,803,000	$ 40,556,000	$ 33,634,000	26,843,000	$ 24,847,000	$ 21,021,000	$ 20,217,000	161,602,000	92,928,000	$ 91,948,000
Goodwill impairments										0
Goodwill		$ 40,044,000				$ 1,585,000				40,044,000	$ 1,585,000
General and Administrative Expense [Member]
Business Acquisition [Line Items]
Acquisition costs										$ 2,100,000
TxCell S.A. [Member]
Business Acquisition [Line Items]
Acquisition date										Oct. 01, 2018
Number of ordinary shares acquired \| shares	13,519,036	11,528,635
Percentage of share capital and voting rights acquired		98.20%								98.20%
Purchase price per share \| (per share)	$ 2.99	$ 2.94								$ 2.94			€ 2.58
Estimated fair value of free shares	$ 200,000									$ 1,300,000
Loan deemed to be part of purchase consideration	5,200,000
Cash paid to ordinary shares acquired	40,500,000
Purchase consideration	$ 45,911,000	$ 33,900,000								$ 80,400,000
Revenues		0
Operating expenses		$ 3,700,000
Fair value percentage at acquirer recognizes and consolidates assets acquired, liabilities assumed, and any non-controlling interest	100.00%
Number of shares not purchased by the acquirer \| shares	11,981,867
Number of remaining outstanding share owned by sellers \| shares		453,000								453,000
Goodwill impairment loss										$ 0
Goodwill	$ 38,995,000
Changes in goodwill										$ 0
TxCell S.A. [Member] \| IPR&D [Member]
Business Acquisition [Line Items]
Identified intangible assets	$ 55,000,000
TxCell S.A. [Member] \| SPA and TOA [Member]
Business Acquisition [Line Items]
Percentage of equity interests agreed to acquire															100.00%
Number of free shares held by the holders \| shares	477,000
Purchase price per share \| (per share)	$ 2.99													€ 2.58
Exchange rate on purchase price	1.16
TxCell S.A. [Member] \| SPA and TOA [Member] \| Minimum [Member]
Business Acquisition [Line Items]
Purchase price per share \| € / shares														€ 2.58
TxCell S.A. [Member] \| SPA and TOA [Member] \| Option Pricing Method [Member]
Business Acquisition [Line Items]
Estimated fair value of free shares	$ 200,000
TxCell S.A. [Member] \| SPA [Member]
Business Acquisition [Line Items]
Number of ordinary shares acquired \| shares	13,519,036
Percentage of share capital and voting rights acquired	53.00%