Debt instrument prepayment percentage.

No definition available.

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Period Type:	instant

- Definition

Debt instrument prepayment premium, description.

+ References

No definition available.

+ Details

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- Definition

Percentage of market capitalization.

+ References

No definition available.

+ Details

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- Definition

Percentage required to pay an additional exit fee on principal amount.

+ References

No definition available.

+ Details

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- Definition

Revenue from contract with customer excluding assessed tax in next twelve months.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Revenue from contract with customer excluding assessed tax in year two.

+ References

No definition available.

+ Details

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Namespace Prefix:	chrs_
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Period Type:	duration

- Definition

Revenue from contract with customer excluding assessed tax thereafter.

+ References

No definition available.

+ Details

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Namespace Prefix:	chrs_
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Balance Type:	credit
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

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-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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

- Definition

Amount of the fee that accompanies borrowing money under the debt instrument.

+ 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 210.5-02.22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	debit
Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870

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

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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

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Amount, after accumulated amortization, of debt discount (premium).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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Balance Type:	debit
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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
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Convertible Notes and Term Loan - Term Loan Narrative (Details) - USD ($) $ in Thousands			6 Months Ended	12 Months Ended
	Apr. 13, 2020	Jan. 07, 2019	Jun. 30, 2020	Dec. 31, 2021	Dec. 31, 2019	Jan. 01, 2020	Feb. 29, 2016
Term Loan
Debt Instrument [Line Items]
Total term of the loan			4 years 6 months
Aggregate principal amount			$ 75,000		$ 75,000
Effective interest rate			10.47%
Net sales					$ 250,000
Debt instrument maturity date			Jan. 07, 2025
Percentage required to pay an additional exit fee on principal amount		4.00%
Consolidated net sales, 2020			$ 125,000
Consolidated net sales, thereafter			150,000
Unamortized debt discount and debt issuance costs on Term Loan			$ 3,941
Term Loan \| Paid on or Prior to the Three Year Anniversary of Closing Date
Debt Instrument [Line Items]
Prepayment premium, description			with respect to any prepayment paid or required to be paid on or prior to the three year anniversary of the Credit Agreement Closing Date, 5.00% of the Borrowings prepaid or required to be prepaid, plus all required interest payments that would have been due on the Borrowings prepaid or required to be prepaid through and including the three year anniversary of the Term Loan Closing Date
Prepayment premium percentage			5.00%
Term Loan \| Paid after the Three Year but on or Prior to the Four Year Anniversary of Closing Date
Debt Instrument [Line Items]
Prepayment premium, description			with respect to any prepayment paid or required to be paid after the three year anniversary of the Term Loan Closing Date but on or prior to the four year anniversary of the Term Loan Closing Date, 5.00% of the Borrowings prepaid or required to be prepaid
Prepayment premium percentage			5.00%
Term Loan \| Paid after the Four Year but on or Prior to the Five Year Anniversary of Closing Date
Debt Instrument [Line Items]
Prepayment premium, description			with respect to any prepayment paid or required to be paid after the four year anniversary of the Term Loan Closing Date but on or prior to the five year anniversary of the Term Loan Closing Date, 2.50% of the Borrowings prepaid or required to be prepaid
Prepayment premium percentage			2.50%
Term Loan \| Paid Thereafter
Debt Instrument [Line Items]
Prepayment premium, description			with respect to any prepayment paid or required to be prepaid thereafter, 1.25% of the Borrowings prepaid or required to be prepaid
Prepayment premium percentage			1.25%
Term Loan \| Maximum
Debt Instrument [Line Items]
Aggregate principal amount	$ 230,000
Percentage Of Market Capitalization	20.00%
Term Loan \| Maximum \| Scenario Forecast
Debt Instrument [Line Items]
Net sales				$ 375,000
Term Loan \| Minimum
Debt Instrument [Line Items]
Consolidated net sales, 2019			$ 70,000
Term Loan \| LIBOR
Debt Instrument [Line Items]
Effective interest rate		7.00%				6.75%
Convertible Notes
Debt Instrument [Line Items]
Total term of the loan			1 year 9 months
Lender
Debt Instrument [Line Items]
Aggregate principal amount							$ 75,000
Lender \| Term Loan
Debt Instrument [Line Items]
Total term of the loan		6 years
Aggregate principal amount		$ 75,000	$ 75,000
Payment of closing fee to the lenders in form of origination issue discount		$ 1,100