Accounting policies.

No definition available.

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- Definition

Number of customers.

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13531-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13537-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

+ Details

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

+ Details

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Period Type:	instant

- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

+ Details

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- Details

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- Details

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- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_SalesRevenueNetMember
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- Details

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Summary of Significant Accounting Policies - Additional Information (Details) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019 USD ($) Customer	Sep. 30, 2018 Customer	Sep. 30, 2019 USD ($) Customer	Sep. 30, 2018 Customer	Dec. 31, 2018 Customer	Jan. 01, 2019 USD ($)
Accounting Policies [Line Items]
Operating lease right-of-use asset \| $	$ 627		$ 627			$ 900
Operating lease liability \| $	$ 677		$ 677			$ 900
Customer Concentration Risk \| Accounts Receivable
Accounting Policies [Line Items]
Number of customers \| Customer			1		1
Customer Concentration Risk \| Revenues
Accounting Policies [Line Items]
Number of customers \| Customer	2	2	2	2
Customer One \| Customer Concentration Risk \| Accounts Receivable
Accounting Policies [Line Items]
Concentration risk percentage			17.00%		77.00%
Customer One \| Customer Concentration Risk \| Revenues
Accounting Policies [Line Items]
Concentration risk percentage	20.00%	23.00%	20.00%	22.00%
Customer Two \| Customer Concentration Risk \| Revenues
Accounting Policies [Line Items]
Concentration risk percentage	14.00%	15.00%	14.00%	15.00%