The payment period of contingent value rights under business combination.

No definition available.

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- Definition

The percent of milestone and royalty based payments payable as part of contingent value rights under business combination.

+ References

No definition available.

+ Details

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- Definition

The percent of upfront payments payable as part of contingent value rights under business combination.

+ References

No definition available.

+ Details

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- Definition

The number of contingent value rights issuable in consideration for each share under business combination.

+ References

No definition available.

+ Details

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

- Definition

Number of outlicensed partnership program in a business combination.

+ References

No definition available.

+ Details

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Namespace Prefix:	chrs_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of shares issued in exchange of each share of acquiree in a business combination.

+ References

No definition available.

+ Details

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

- Definition

Number of shares issued to former employees of acquiree.

+ References

No definition available.

+ Details

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Balance Type:	na
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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
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-Publisher FASB
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+ Details

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Period Type:	duration

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

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Period Type:	duration

- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

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- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

+ Details

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Period Type:	duration

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

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- Details

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Surface Acquisition (Details) $ / shares in Units, $ in Thousands		4 Months Ended	12 Months Ended
	Sep. 08, 2023 USD ($) item $ / shares shares	Dec. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Surface Acquisition
Goodwill		$ 943	$ 943	$ 943
Surface Oncology, Inc.
Surface Acquisition
Business Combination, Number of Shares Issued in Exchange of Each Share of Acquiree \| shares	0.1960
Share price \| $ / shares	$ 5.2831
Contingent value right per share \| item	1
Contingent value rights payment period	10 years
Business combination consideration transferred	$ 64,596
Business Combination, Number of Shares Issued to Former Employees of Acquiree shares \| shares	161,100
Goodwill	$ 0
Business Combination, Number of Out Licensed Partnership Program \| item	2
Revenue of Acquiree since Acquisition Date		0
Earnings or Loss of Acquiree since Acquisition Date		$ (5,900)
Acquisition related costs			$ 5,100
Surface Oncology, Inc. \| Surface GSK Agreement
Surface Acquisition
Milestone and royalty based CVR payments (as percent)	70.00%
Surface Oncology, Inc. \| Surface Novartis Agreement
Surface Acquisition
Milestone and royalty based CVR payments (as percent)	70.00%
Surface Oncology, Inc. \| Surface's SRF114 proprietary drug product candidate
Surface Acquisition
Upfront payment based CVR payments (as percent)	25.00%
Surface Oncology, Inc. \| Surface's SRF388 proprietary drug product candidate
Surface Acquisition
Upfront payment based CVR payments (as percent)	50.00%