Debt instrument prepayment percentage.

No definition available.

Name:	chrs_DebtInstrumentPrepaymentPercentage
Namespace Prefix:	chrs_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

Name:	chrs_PercentageRequiredToPayAdditionalExitFeeOnPrincipalAmount
Namespace Prefix:	chrs_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
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

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	srt_CounterpartyNameAxis=chrs_HealthcareRoyaltyPartnersIIILPMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

Debt Obligations - 2025 Term Loan - Narrative (Details) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended
	Jan. 07, 2019	Jan. 31, 2022	Mar. 31, 2022
Debt Instrument
Outstanding amount paid off			$ 81,750
Loss on debt extinguishment			(6,222)
Lender \| 2025 Term Loan
Debt Instrument
Total term of the loan	6 years
Principal amount	$ 75,000	$ 75,000
Outstanding amount paid off		$ 81,900
Prepayment premium percentage		5.00%
Percentage required to pay an additional exit fee on principal amount		4.00%
Loss on debt extinguishment		$ (6,200)
Interest expense			$ 200