Debt Instrument, Covenant, Interest Coverage Ratio, Minimum Threshold

No definition available.

Name:	snbr_DebtInstrumentCovenantInterestCoverageRatioMinimumThreshold
Namespace Prefix:	snbr_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Covenant, Minimum Liquidity

+ References

No definition available.

+ Details

Name:	snbr_DebtInstrumentCovenantMinimumLiquidity
Namespace Prefix:	snbr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Debt Instrument, Covenant, Net Leverage Ratio, Maximum Threshold

+ References

No definition available.

+ Details

Name:	snbr_DebtInstrumentCovenantNetLeverageRatioMaximumThreshold
Namespace Prefix:	snbr_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Covenant, Net Leverage Ratio, Minimum Threshold

+ References

No definition available.

+ Details

Name:	snbr_DebtInstrumentCovenantNetLeverageRatioMinimumThreshold
Namespace Prefix:	snbr_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Line Of Credit Facility, Amendment Fee Percentage

+ References

No definition available.

+ Details

Name:	snbr_LineOfCreditFacilityAmendmentFeePercentage
Namespace Prefix:	snbr_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 605
-Name Accounting Standards Codification
-Section 55
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477548/944-605-55-15

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 605
-Name Accounting Standards Codification
-Section 55
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477548/944-605-55-12

+ Details

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

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

Name:	us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity
Namespace Prefix:	us-gaap_
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/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	snbr_DebtCovenantPeriodAxis=snbr_DebtCovenantPeriodOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	snbr_DebtCovenantPeriodAxis=snbr_DebtCovenantPeriodTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	snbr_DebtCovenantPeriodAxis=snbr_DebtCovenantPeriodThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	snbr_DebtCovenantPeriodAxis=snbr_DebtCovenantPeriodFourMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Credit Agreement - Narrative (Details) $ in Thousands	Mar. 03, 2025 USD ($)	Jun. 29, 2025 USD ($)	Jun. 28, 2025 USD ($)	Dec. 28, 2024 USD ($)
Line of Credit Facility [Line Items]
Outstanding letters of credit			$ 6,847	$ 7,147
Subsequent Event
Line of Credit Facility [Line Items]
Outstanding letters of credit		$ 9,000
Line of Credit
Line of Credit Facility [Line Items]
Current borrowing capacity			673,000
Total commitment amount			$ 1,000,000
Minimum liquidity	$ 40,000
Net leverage ratio, minimum threshold	4.50
Amendment fee percentage	0.20%
Line of Credit \| Debt Covenant Period One
Line of Credit Facility [Line Items]
Net leverage ratio, maximum threshold	4.75
Minimum interest coverage ratio	1.90
Line of Credit \| Debt Covenant Period Two
Line of Credit Facility [Line Items]
Net leverage ratio, maximum threshold	4.50
Minimum interest coverage ratio	2.10
Line of Credit \| Debt Covenant Period Three
Line of Credit Facility [Line Items]
Net leverage ratio, maximum threshold	4.35
Minimum interest coverage ratio	3.00
Line of Credit \| Debt Covenant Period Four
Line of Credit Facility [Line Items]
Net leverage ratio, maximum threshold	4.00