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

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-Section 50
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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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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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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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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
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Number of promissory notes settled upon the closing of the merger.

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Number of shares surrendered by former management of acquiree to reimburse the entity for required payroll tax withholdings.

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Mergers and Acquisitions - Medistem - Additional Information (Details) - Medistem, Inc. $ in Thousands	1 Months Ended		12 Months Ended
	Nov. 30, 2016	Mar. 31, 2014 USD ($) note shares	Dec. 31, 2016 USD ($)	Dec. 31, 2014 USD ($)
Business Acquisition [Line Items]
Percentage of outstanding common stock acquired		100.00%
Business combination, consideration paid, shares issued \| shares		714,144
Cash		$ 4,920
Number of promissory notes settled \| note		2
Total consideration transferred		$ 24,995
Shares surrendered to pay withholding taxes shares \| shares		17,695
Expected useful life of intangible asset	10 years
Business combination, acquisition related cost			$ 680
Selling, general and administrative
Business Acquisition [Line Items]
Business combination, acquisition related cost				$ 310
Promissory Notes
Business Acquisition [Line Items]
Total consideration transferred		$ 707