Condensed Consolidated Statement of Shareholder's Equity (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Public Offering
Issuance costs	$ 9,212	$ 5,110
Cowen and Company, LLC \| Private Placement
Issuance costs	$ 79		$ 2,110

Amount of decrease in additional paid in capital (APIC) resulting from direct costs associated with issuing stock. Includes, but is not limited to, legal and accounting fees and direct costs associated with stock issues under a shelf registration.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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