Discount on the revenue participation liability, resulting from a derivative instrument.

No definition available.

Name:	chrs_DiscountOnRevenueParticipationLiabilityFromDerivativeInstrument
Namespace Prefix:	chrs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Issuance costs on the revenue participation liability.

+ References

No definition available.

+ Details

Name:	chrs_IssuanceCostsOnRevenueParticipationLiability
Namespace Prefix:	chrs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow to buy out the right to receive future payments in accordance with agreement entered into by the company.

+ References

No definition available.

+ Details

Name:	chrs_PaymentsToBuyOutRightToReceiveFuturePayments
Namespace Prefix:	chrs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Revenue Purchase and Sale Agreement purchase price.

+ References

No definition available.

+ Details

Name:	chrs_RevenuePurchaseAndSaleAgreementCertainConditionsPurchasePriceMultiplier
Namespace Prefix:	chrs_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Revenue Purchase and Sale Agreement purchase price.

+ References

No definition available.

+ Details

Name:	chrs_RevenuePurchaseAndSaleAgreementPurchasePrice
Namespace Prefix:	chrs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The percent to be received pertaining to the sales of the companies products and services.

+ References

No definition available.

+ Details

Name:	chrs_RevenuePurchaseAndSaleAgreementRightToReceivePercent
Namespace Prefix:	chrs_
Data Type:	dtr-types:percentItemType
Balance Type:	na
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/exampleRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 55
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482949/835-30-55-8

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(a)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482900/835-30-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-6

+ Details

Name:	us-gaap_DebtInstrumentInterestRateEffectivePercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
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

Name:	us-gaap_EmbeddedDerivativeLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=chrs_RevenuePurchaseAndSaleAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=chrs_UdenycaBusinessMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ProductOrServiceAxis=chrs_UdenycaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ProductOrServiceAxis=chrs_UdenycaAndLoqtorziMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ProductOrServiceAxis=chrs_LoqtorziMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Financial Liabilities - Revenue Purchase and Sale Agreement - Narrative (Details) - USD ($) $ in Millions	Apr. 15, 2025	Mar. 31, 2026	May 08, 2024
Embedded Derivative [Line Items]
Effective interest rate		2.10%
Revenue Purchase and Sale Agreement
Embedded Derivative [Line Items]
Revenue Purchase and Sale Agreement, Purchase price			$ 37.5
Purchase price multiplier			2.25
Discount on revenue participation liability from allocation of purchase price to the embedded derivative		$ 9.2
Issuance costs on revenue participation liability		$ 1.4
UDENYCA \| Revenue Purchase and Sale Agreement
Embedded Derivative [Line Items]
Payments to buy out right to receive future payments	$ 47.7
UDENYCA \| Revenue Purchase and Sale Agreement
Embedded Derivative [Line Items]
Revenue payment, Percentage of U.S. net sales			5.00%
UDENYCA and LOQTORZI \| Revenue Purchase and Sale Agreement
Embedded Derivative [Line Items]
Revenue payment, Percentage of U.S. net sales			0.50%
LOQTORZI
Embedded Derivative [Line Items]
Effective interest rate		27.40%