Amount of lease rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

No definition available.

+ Details

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Namespace Prefix:	cert_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Remaining lease term of operating and capital leases, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	cert_OperatingLeaseAndCapitalLeaseRemainingLeaseTerm
Namespace Prefix:	cert_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of accumulated amortization of right-of-use asset from finance lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918686-209980

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918638-209977

+ Details

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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

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

- Details

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- Details

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Leases (Details) - USD ($) $ in Thousands	12 Months Ended
Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Leases
Capital lease accumulated amortization		$ 946
Operating lease rent expense		$ 6,534	$ 6,377
Minimum
Leases
Remaining operating and capital lease term	1 year
Maximum
Leases
Remaining operating and capital lease term	7 years