Contingently Issuable Common Stock (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended
Dec. 10, 2010	Mar. 31, 2019
Nelix Milestones
Business Acquisition [Line Items]
Number of shares contingently issuable (in shares)	1,020,000
Estimated fair value of contingent payment	$ 28.2
PMA Milestone
Business Acquisition [Line Items]
Number of shares contingently issuable (in shares)		333,149
Common shares value		$ 15.0
Share price (in dollars per share)		$ 45
Closing stock price (in dollars per share)		$ 6.61
Average daily closing stock price		30 days
Days prior to milestone achievement announcement		5 days
Contingent consideration, at fair value hypothetical value		$ 2.2

Business Acquisition, Contingent Consideration, at Fair Value Hypothetical Value

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- Definition

Business Acquisition, Contingent Consideration, Closing Stock Price Per Share

+ References

No definition available.

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- Definition

Business Acquisition, Contingent Consideration, Days Prior To Milestone Achievement Announcement

+ References

No definition available.

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- Definition

Weighted Average Number Of Shares, Daily Average Closing Stock Price

+ References

No definition available.

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- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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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

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

Fair value of contingent consideration in a business combination that is classified in shareholders' equity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Shares issuable for little or no cash consideration upon the satisfaction of certain conditions (contingently issuable shares) are considered outstanding common shares and included in the computation of basic Earnings Per Share as of the date that all necessary conditions have been satisfied (in essence, when issuance of the shares is no longer contingent). Outstanding common shares that are contingently returnable (that is, subject to recall) are treated in the same manner as contingently issuable shares. Contingently issuable shares include shares that (a) will be issued in the future upon the satisfaction of specified conditions, (b) have been placed in escrow and all or part must be returned if specified conditions are not met, or (c) have been issued but the holder must return all or part if specified conditions are not met. The number of contingently issuable shares is determined by relating the portion of time within a reporting period that these shares have been outstanding to the total time in that period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=109260490&loc=d3e2646-109256

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