Business acquisition estimated fair value assets of free shares.

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- Definition

Business acquisition estimated fair value liabilities of free shares.

+ References

No definition available.

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- Definition

Business acquisition, estimated fair value of free shares.

+ References

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- Definition

Business acquisition exchange rate on purchase price.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Business acquisition, number of shares acquired.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Business acquisition, percentage of equity interests agreed to acquire.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Business combination, loan adjusted in purchase consideration.

+ References

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

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

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.

+ 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

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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- 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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Acquisition of Txcell S.A. - Additional Information (Detail)		3 Months Ended		12 Months Ended
	Oct. 01, 2018 USD ($) $ / shares shares	Mar. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares	Mar. 31, 2019 € / shares	Dec. 31, 2018 € / shares shares	Oct. 01, 2018 € / shares	Jul. 20, 2018
Business Acquisition [Line Items]
Purchase price per share \| $ / shares	$ 2.99
Goodwill impairments		$ 0		$ 0
Number of shares not purchased by the acquirer \| shares	11,981,867
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%		98.20%
Number of remaining outstanding share owned by sellers \| shares		453,000	453,000	453,000		453,000
Purchase price per share \| (per share)	$ 2.99		$ 2.94	$ 2.94	€ 2.36	€ 2.58
Loan deemed to be part of purchase consideration	$ 5,200,000
Cash paid to ordinary shares acquired	40,500,000
Fair value of consideration payable	200,000	$ 700,000
Purchase consideration	$ 45,911,000		$ 33,900,000	$ 80,400,000
Fair value percentage at acquirer recognizes and consolidates assets acquired, liabilities assumed, and any non-controlling interest	100.00%
Consideration payable	$ 45,911,000		$ 33,900,000	$ 80,400,000
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	0.0116
Estimated fair value asset of free shares		$ 400,000
TxCell S.A. [Member] \| SPA and TOA [Member] \| Option Pricing Method [Member]
Business Acquisition [Line Items]
Estimated fair value liability of free shares	$ 200,000
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 [Member]
Business Acquisition [Line Items]
Number of ordinary shares acquired \| shares	13,519,036
Percentage of share capital and voting rights acquired	53.00%