Lessee, Operating Lease, Number Of Renewal Options

No definition available.

Name:	snti_LesseeOperatingLeaseNumberOfRenewalOptions
Namespace Prefix:	snti_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Tenant Improvement Allowance

+ References

No definition available.

+ Details

Name:	snti_TenantImprovementAllowance
Namespace Prefix:	snti_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Tenant Improvement Allowance Utilized

+ References

No definition available.

+ Details

Name:	snti_TenantImprovementAllowanceUtilized
Namespace Prefix:	snti_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Tenant Improvement Reimbursements

+ References

No definition available.

+ Details

Name:	snti_TenantImprovementReimbursements
Namespace Prefix:	snti_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147478964/842-20-50-3

+ Details

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

- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147478964/842-20-50-3

+ Details

Name:	us-gaap_LesseeOperatingLeaseRenewalTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

+ Details

Name:	us-gaap_LesseeOperatingLeaseTermOfContract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_LeaseContractualTermAxis=snti_CorporateHeadquartersMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LeaseContractualTermAxis=snti_AlamedaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Operating Leases - Narrative (Details) $ in Millions	3 Months Ended		6 Months Ended		23 Months Ended
Operating Leases - Narrative (Details) $ in Millions	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) tradingDay	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jun. 03, 2021
Lessee, Lease, Description [Line Items]
Lease term						11 years
Corporate Headquarters
Lessee, Lease, Description [Line Items]
Lease term	8 years		8 years		8 years
Lease renewal term	8 years		8 years		8 years
Alameda
Lessee, Lease, Description [Line Items]
Lease term	11 years		11 years		11 years
Lease renewal term	5 years		5 years		5 years
Number of renewal options \| tradingDay			2
Tenant improvement allowance received	$ 1.0	$ 5.6	$ 2.0	$ 8.1
Tenant improvement allowance	$ 17.5		$ 17.5		$ 17.5
Tenant improvement allowance utilized					$ 16.2