Short-term Loans - PPP loan (Details) - Loans Payable [Member] - Paycheck Protection Program, CARES Act [Member] - USD ($) $ in Thousands			12 Months Ended
Feb. 08, 2021	Apr. 09, 2020	Dec. 31, 2020
Short-Term Debt [Line Items]
Proceeds		$ 1,680
Percentage of PPP loan proceeds were used for payroll related expenses (as a percent)			100.00%
Debt instrument, decrease, forgiveness	$ 1,680

The percentage of loan proceeds from Paycheck Protection Program which were used to pay payroll related expenses.

No definition available.

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- Definition

Decrease for amounts of indebtedness forgiven by the holder of the debt instrument.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow from a borrowing having initial term of repayment within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585

+ Details

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Balance Type:	debit
Period Type:	duration

- 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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- Details

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- Details

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