Commitments - Torreya Agreement (Details) - Advisory services - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Other Commitments [Line Items]
Additional consultant fee payable, percentage of perpetuity	3.375%
Sponsor fees	$ 353	$ 212
Recorded liabilities	$ 211

Other Commitment, Milestone Payment Percentage of Total Consideration With Payment

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- Definition

Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due after one year (or beyond the operating cycle if longer), including liabilities for compensation costs, fringe benefits other than pension and postretirement obligations, rent, contractual rights and obligations, and statutory obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.24)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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.

+ Details

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- Definition

Fees paid to advisors who provide certain management support and administrative oversight services including the organization and sale of stock, investment funds, limited partnerships and mutual funds.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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