A roll forward is a reconciliation of a concept from the beginning of a period to the end of the period.

No definition available.

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13476-108611

+ Details

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- Definition

Amount of expense (income) related to adjustment to fair value of warrant liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section 25
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=6939902&loc=d3e20148-110875

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

+ Details

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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

The fair value of stock issued in noncash financing activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586

+ Details

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Period Type:	duration

- Definition

Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Recurring Basis (Details) - USD ($) $ in Thousands	3 Months Ended
- Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Dec. 31, 2017
Liabilities that are measured at fair value on a recurring basis
Warrants	$ 397		$ 397	$ 397
Change in the estimated fair value of warrant liabilities
Balance at December 31, 2017	397
Increase in fair value	2,907	$ (107)
Warrant exercise	(2,000)	$ 0
Balance at March 31, 2018	397
Silicon Valley Bank \| Debt Financing Agreement and Term Loan
Change in the estimated fair value of warrant liabilities
Debt instrument, fair value			17,200	17,200
Warrants
Liabilities that are measured at fair value on a recurring basis
Warrants	1,014		1,921	1,014
Change in the estimated fair value of warrant liabilities
Balance at December 31, 2017	1,014
Increase in fair value	2,907
Warrant exercise	(2,000)
Balance at March 31, 2018	1,921
Warrants \| Recurring
Liabilities that are measured at fair value on a recurring basis
Warrants	1,014		1,921	1,014
Change in the estimated fair value of warrant liabilities
Balance at December 31, 2017	1,014
Balance at March 31, 2018	1,921
Warrants \| Recurring \| Level 1
Liabilities that are measured at fair value on a recurring basis
Warrants	0		0	0
Change in the estimated fair value of warrant liabilities
Balance at December 31, 2017	0
Balance at March 31, 2018	0
Warrants \| Recurring \| Level 2
Liabilities that are measured at fair value on a recurring basis
Warrants	1,014		1,921	1,014
Change in the estimated fair value of warrant liabilities
Balance at December 31, 2017	1,014
Balance at March 31, 2018	1,921
Warrants \| Recurring \| Level 3
Liabilities that are measured at fair value on a recurring basis
Warrants	0		$ 0	$ 0
Change in the estimated fair value of warrant liabilities
Balance at December 31, 2017	0
Balance at March 31, 2018	$ 0