Research Collaboration and License Agreement, Option to Terminate

No definition available.

Name:	lsta_ResearchCollaborationAndLicenseAgreementOptionToTerminate
Namespace Prefix:	lsta_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Revenue, Performance Obligation, Percentage of Net Sale

+ References

No definition available.

+ Details

Name:	lsta_RevenuePerformanceObligationPercentageOfNetSale
Namespace Prefix:	lsta_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Revenue, Performance Obligation, Percentage of Sublicensing Revenues

+ References

No definition available.

+ Details

Name:	lsta_RevenuePerformanceObligationPercentageOfSublicensingRevenues
Namespace Prefix:	lsta_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Revenue, Remaining Performance Obligation, Variable Consideration Amount

+ References

No definition available.

+ Details

Name:	lsta_RevenueRemainingPerformanceObligationVariableConsiderationAmount
Namespace Prefix:	lsta_
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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 808
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479402/808-10-50-1

+ Details

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

- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479837/606-10-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-8

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479837/606-10-45-2

+ Details

Name:	us-gaap_ContractWithCustomerLiability
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of revenue from collaborative arrangement. Excludes revenue from contract with customer under Topic 606.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 808
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479402/808-10-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 3
-SubTopic 10
-Topic 808
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479428/808-10-45-3

+ Details

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

- Details

Name:	us-gaap_TypeOfArrangementAxis=lsta_ExclusiveLicenseAndCollaborationAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	srt_ProductOrServiceAxis=us-gaap_LicenseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Research Collaboration and License Agreement (Details) - USD ($)		1 Months Ended	3 Months Ended		9 Months Ended
	Sep. 14, 2022	Feb. 28, 2021	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue from contract			$ 0	$ 0	$ 0	$ 0
Exclusive License and Collaboration Agreement \| Qilu \| License
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Contract with customer, liability		$ 10,000,000
Revenue from contract	$ 5,000,000
Option to terminate		60 days
Exclusive License and Collaboration Agreement \| Qilu \| License \| Minimum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Variable consideration amounts, milestones		$ 95,000,000
Percentage of net sale		10.00%
Percentage of sublicensing revenues		12.00%
Exclusive License and Collaboration Agreement \| Qilu \| License \| Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Variable consideration amounts, milestones		$ 125,000,000
Percentage of net sale		15.00%
Percentage of sublicensing revenues		35.00%