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Fair Value Measurements - Additional Information (Detail) - TxCell S.A. [Member] - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Oct. 01, 2018
Schedule Of Available For Sale Securities [Line Items] |  |
Liability recorded on acquisition date |  | $ 4,933
Share Purchase Agreement and Tender Offer Agreement [Member] |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Number of free shares held by the holders |  | 477,000
Liability recorded on acquisition date |  | $ 200
Increase in fair value of free shares | $ 500 |

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- Definition Amount of liabilities assumed at the acquisition date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472 + Details
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- Details
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