Debt instrument, available amount upon condition.

No definition available.

Name:	cers_DebtInstrumentAvailableAmountUponCondition
Namespace Prefix:	cers_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt instrument interest only payments due period.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Debt instrument interest only payments extended period.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Debt instrument principal and declining interest payments additional period.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Number of equal tranches.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

+ Details

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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

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+ Details

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

- Definition

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

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ 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

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	instant

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Period Type:

- Details

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Period Type:

- Details

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Period Type:

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Period Type:

- Details

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Namespace Prefix:
Data Type:	na
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Period Type:

- Details

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Namespace Prefix:
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Period Type:

- Details

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Period Type:

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Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=us-gaap_RevolvingCreditFacilityMember
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Debt - Additional Information (Detail)	Mar. 31, 2023 USD ($)	Mar. 30, 2023 USD ($)	Mar. 29, 2019 USD ($) Tranche	Mar. 31, 2024 USD ($)	Mar. 27, 2024 USD ($)	Dec. 31, 2023 USD ($)	Sep. 01, 2023 USD ($)
Prior Term Loan Credit Agreement
Debt Instrument [Line Items]
Term loan, face amount			$ 70,000,000
Number of loan tranches \| Tranche			3
Debt instrument maturity date			Mar. 01, 2024
Prior Term Loan Credit Agreement \| Term Loan
Debt Instrument [Line Items]
Debt instrument floating interest rate percentage			1.80%
Prior Term Loan Credit Agreement \| Tranche 1
Debt Instrument [Line Items]
Term loan, face amount	$ 40,000,000		$ 40,000,000
Prior Term Loan Credit Agreement \| Tranche 2 \| Term Loan
Debt Instrument [Line Items]
Term loan, face amount	15,000,000		$ 15,000,000
Prior Term Loan Credit Agreement \| Tranche 3 \| Term Loan
Debt Instrument [Line Items]
Debt instrument maturity date			Dec. 31, 2021
Loan and security agreement available upon revenue achievement			$ 15,000,000
Term Loan Credit Agreement
Debt Instrument [Line Items]
Term loan, face amount	$ 75,000,000
Term Loan Credit Agreement \| SOFR
Debt Instrument [Line Items]
Variable rate	6.50%
Term Loan Credit Agreement \| Term Loan
Debt Instrument [Line Items]
Effective interest rate				12.20%
Debt instruments, interest only payments due	36 months
Principal plus declining interest payments	24 months
Debt instrument interest only payments extended period	12 months
Term Loan Credit Agreement \| Tranche 1 \| Floor
Debt Instrument [Line Items]
Variable rate	1.00%
Term Loan Credit Agreement \| Tranche 2 \| Floor
Debt Instrument [Line Items]
Variable rate	1.00%
Term Loan Credit Agreement \| Tranche 3
Debt Instrument [Line Items]
Term loan, face amount					$ 5,000,000		$ 5,000,000
Loan and security agreement available upon revenue achievement							$ 5,000,000
Term Loan Credit Agreement \| Tranche 3 \| Floor
Debt Instrument [Line Items]
Variable rate	1.00%
Term Loan Credit Agreement \| Tranche 3 \| Term Loan
Debt Instrument [Line Items]
Loan and security agreement available upon revenue achievement	$ 10,000,000
Term Loan Credit Agreement \| Tranche 4 \| Floor
Debt Instrument [Line Items]
Variable rate	1.00%
Term Loan Credit Agreement \| Tranche 4 \| Term Loan
Debt Instrument [Line Items]
Loan and security agreement available upon revenue achievement	$ 10,000,000
Prior Revolving Loan Credit Agreement
Debt Instrument [Line Items]
Loan and security agreement available upon revenue achievement		$ 5,000,000
Borrowing limit		$ 15,000,000
Prior Revolving Loan Credit Agreement \| Term Loan
Debt Instrument [Line Items]
Debt instrument maturity date		Mar. 01, 2024
Revolving Loan Credit Agreement
Debt Instrument [Line Items]
Term loan, face amount				$ 20,100,000		$ 20,000,000
Loan and security agreement available upon revenue achievement	15,000,000
Borrowing limit	$ 20,000,000
Revolving Loan Credit Agreement \| SOFR
Debt Instrument [Line Items]
Debt instrument floating interest rate percentage			0.10%
Variable rate	3.75%
Revolving Loan Credit Agreement \| Floor
Debt Instrument [Line Items]
Variable rate	1.00%