Shares of stock issued as a result of the exercise of warrants.

No definition available.

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Period Type:	duration

- Definition

Number of warrants exercised during the current period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

+ Details

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Period Type:	instant

- 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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Balance Type:	na
Period Type:	duration

- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

+ Details

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Period Type:	instant

- Definition

Number of warrants or rights outstanding.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Fair value portion of warrants not settleable in cash classified as 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=117815213&loc=d3e19207-110258

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Period Type:	instant

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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Balance Type:
Period Type:

- Details

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Data Type:	na
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Period Type:

- Details

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Warrants (Details) - USD ($)		12 Months Ended
Warrants (Details) - USD ($)	Jun. 30, 2014	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Warrants
Proceeds from issuance of convertible notes		$ 280,000,000	$ 0	$ 0
Common stock
Warrants
Number of shares issued upon exercise of warrants (in shares)			5,813	159,944
Warrant
Warrants
Warrants exercisable into stock (in shares)	8,230
Exercise price (in dollars per share)	$ 15.19
Fair value of warrants	$ 100,000
Number of warrants exercised (in shares)			8,230	177,123
Warrants outstanding (in shares)		0	0
Term A Loan
Warrants
Maximum borrowing capacity	5,000,000.0
Term A Loan \| Secured promissory notes
Warrants
Proceeds from issuance of convertible notes	$ 5,000,000.0