XML 65 R51.htm IDEA: XBRL DOCUMENT
v3.20.2

COVID-19 Pandemic (Details) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 26, 2020 | Jun. 27, 2020 | Sep. 26, 2020
Unusual or Infrequent Item, or Both [Line Items] |  |  |
Increase (decrease) in net sales (as a percent) |  | (20.00%) | 3.00%
Increase in net income (as a percent) |  |  | 35.00%
Average |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |
Average percentage of stores that are open (more than) | 98.00% | 47.00% |

X
- Definition Increase (Decrease) In Net Income, Percentage + References No definition available. + Details
Name: | snbr_IncreaseDecreaseInNetIncomePercentage
Namespace Prefix: | snbr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Increase (Decrease) In Net Sales, Percentage + References No definition available. + Details
Name: | snbr_IncreaseDecreaseInNetSalesPercentage
Namespace Prefix: | snbr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage Of Stores That Are Open, COVID-19 + References No definition available. + Details
Name: | snbr_PercentageOfStoresThatAreOpenCOVID19
Namespace Prefix: | snbr_
Data Type: | num:percentItemType
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 No definition available. + Details
Name: | us-gaap_UnusualOrInfrequentItemLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | srt_RangeAxis=srt_WeightedAverageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |