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

Warrants Exercised For Common Stock

+ References

No definition available.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ 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

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
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-Section 50
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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section 25
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=109262497&loc=d3e20148-110875

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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

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ 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 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount of asset associated with funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
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-Topic 210
-SubTopic 20
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226003-175313

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- 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://fasb.org/us-gaap/role/ref/legacyRef
-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

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Fair Value Measurements (Details) - USD ($) $ in Thousands	12 Months Ended
Fair Value Measurements (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2018	Dec. 31, 2017
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value				$ 75,476
Warrant liabilities	$ 397	$ 397		104	$ 397
Change in the estimated fair value of warrant liabilities
Balance at the beginning of the period	397
Increase in fair value (net of expired warrants)	(2,524)	(257)	$ 0
Warrant exercise	(3,538)	0	0
Balance at the end of the period	104	397
Other assets
Liabilities that are measured at fair value on a recurring basis
Interest Receivable and Other Assets				100
Recurring
Liabilities that are measured at fair value on a recurring basis
Repurchase agreements				5,000	0
Assets, fair value				75,476	0
Warrant liabilities	1,014	757	757	0	1,014
Change in the estimated fair value of warrant liabilities
Balance at the beginning of the period	1,014	757
Increase in fair value (net of expired warrants)	2,524	257
Warrant exercise	(3,538)
Balance at the end of the period	0	1,014	$ 757
Recurring \| Level 1
Liabilities that are measured at fair value on a recurring basis
Repurchase agreements				0	0
Assets, fair value				5,838	0
Warrant liabilities	0	0		0	0
Change in the estimated fair value of warrant liabilities
Balance at the beginning of the period	0
Balance at the end of the period	0	0
Recurring \| Level 2
Liabilities that are measured at fair value on a recurring basis
Repurchase agreements				5,000	0
Assets, fair value				69,638	0
Warrant liabilities	1,014	1,014		0	1,014
Change in the estimated fair value of warrant liabilities
Balance at the beginning of the period	1,014
Balance at the end of the period	0	1,014
Recurring \| Level 3
Liabilities that are measured at fair value on a recurring basis
Repurchase agreements				0	0
Assets, fair value				0	0
Warrant liabilities	0	0		0	0
Change in the estimated fair value of warrant liabilities
Balance at the beginning of the period	0
Balance at the end of the period	$ 0	$ 0
Money market funds \| Recurring
Liabilities that are measured at fair value on a recurring basis
Money market funds				5,838	0
Money market funds \| Recurring \| Level 1
Liabilities that are measured at fair value on a recurring basis
Money market funds				5,838	0
Money market funds \| Recurring \| Level 2
Liabilities that are measured at fair value on a recurring basis
Money market funds				0	0
Money market funds \| Recurring \| Level 3
Liabilities that are measured at fair value on a recurring basis
Money market funds				0	0
Commercial paper \| Recurring
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value				30,710	0
Commercial paper \| Recurring \| Level 1
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value				0	0
Commercial paper \| Recurring \| Level 2
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value				30,710	0
Commercial paper \| Recurring \| Level 3
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value				0	0
US Government Debt Securities \| Recurring
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value				10,166	0
US Government Debt Securities \| Recurring \| Level 1
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value				0	0
US Government Debt Securities \| Recurring \| Level 2
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value				10,166	0
US Government Debt Securities \| Recurring \| Level 3
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value				0	0
Asset-backed Securities
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value				10,618
Asset-backed Securities \| Recurring
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value				10,618	0
Asset-backed Securities \| Recurring \| Level 1
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value				0	0
Asset-backed Securities \| Recurring \| Level 2
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value				10,618	0
Asset-backed Securities \| Recurring \| Level 3
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value				0	0
Corporate Note Securities \| Recurring
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value				13,144	0
Corporate Note Securities \| Recurring \| Level 1
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value				0	0
Corporate Note Securities \| Recurring \| Level 2
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value				13,144	0
Corporate Note Securities \| Recurring \| Level 3
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value				$ 0	$ 0