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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)(4)

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

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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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-Topic 805

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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.

+ References

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-Publisher FASB

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-Topic 805

-SubTopic 30

-Section 30

-Paragraph 7

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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-Paragraph 13

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- Definition

Number of promissory notes settled upon the closing of the merger.

+ References

No definition available.

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- Definition

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

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No definition available.

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Mergers and Acquisitions - Medistem - Additional Information (Details) (Medistem, Inc., USD $) In Thousands, except Share data, unless otherwise specified	0 Months Ended	12 Months Ended
	Mar. 06, 2014	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Percentage of outstanding common stock acquired	100.00%
Business acquisition, consideration paid, shares issued	714,144
Consideration paid	$ 4,920
Number of promissory notes settled	2xon_NumberOfPromissoryNotesSettled
Fair value of consideration transferred	24,995
Shares surrendered to pay withholding taxes shares	17,695
Business combination, acquisition related cost		680
Selling, general and administrative
Business Acquisition [Line Items]
Business combination, acquisition related cost		310	370
Promissory Notes
Business Acquisition [Line Items]
Fair value of consideration transferred	$ 707