v3.22.2.2

Debt - Credit agreement (Details) - USD ($) $ in Thousands			3 Months Ended		6 Months Ended
	Jun. 28, 2021	Jan. 19, 2021	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2021	Mar. 30, 2021
Short-term Debt [Line Items]
Debt discount				$ 100
Loss on extinguishment of debt, net			$ 101		$ 2,061
Payment of credit agreement					$ 10,500
Credit agreement
Short-term Debt [Line Items]
Additional borrowing amount		$ 1,000
New debt fair value		10,000
Debt discount						$ 500
Loss on extinguishment of debt, net				$ (3,000)
Credit facility bear interest				2.50%
Other Noncash Expense		$ 100
Payment of credit agreement	$ 10,500
Credit agreement | Series G Warrants
Short-term Debt [Line Items]
Number of shares in exchange of warrant exercise		1,000,000

X

- Definition

The amount of additional borrowing capacity available and that may be drawn under the debt instrument agreement.

+ References

No definition available.

+ Details

Name:	rsls_DebtInstrumentAdditionalBorrowingCapacity
Namespace Prefix:	rsls_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

X

- 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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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount, after accumulated amortization, of debt discount.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

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+ Details

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

X

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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

X

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
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

No definition available.

+ Details

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

X

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

X

- Details

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Namespace Prefix:
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Balance Type:
Period Type: