v3.25.0.1

Summary of Significant Accounting Policies - Credit Risk Concentration (Details)	12 Months Ended
	Dec. 31, 2023 $ / shares
Credit Concentration Risk [Member]
Concentration risk
Money market funds preserve the value of investment per share	$ 1

X

- Definition

The value per share money market funds seek to preserve.

+ References

No definition available.

+ Details

Name:	rsls_MoneyMarketValuePerShare
Namespace Prefix:	rsls_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	duration

X

- 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 954
-SubTopic 310
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478785/954-310-50-2

+ Details

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

X

- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CreditConcentrationRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: