Balance Sheet Components - Accrued and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Balance Sheet Components
Accrued manufacturing and clinical	$ 21,774	$ 30,541
Accrued co-development costs for toripalimab	8,356	1,926
Lease liabilities, current	15,649	12,168
Accrued other	4,318	3,492
Total Accrued and other current liabilities	$ 50,097	$ 48,127

Accrued clinical and manufacturing liabilities current.

No definition available.

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

- Definition

Represent to pertaining the Accrued co-development costs for toripalimab

+ References

No definition available.

+ Details

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

- Definition

Represents lease liabilities for both operating and financing leases.

+ References

No definition available.

+ Details

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

- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ 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 210.5-02.20)
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_AccruedLiabilitiesCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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

- Definition

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

+ References

+ Details

Name:	us-gaap_OtherAccruedLiabilitiesCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant