Repurchases of Common Stock (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 30, 2024	Apr. 01, 2023
Repurchases Of Common Stock [Abstract]
Stock acquired through tax withholding restricted stock	$ 1,000	$ 3,000
Authorized share repurchase program	600,000
Remaining authorized stock purchase plan	$ 348,000

This element represents the amount of total investment in stock repurchased for tax withholding on restricted stock.

No definition available.

Name:	snbr_StockRepurchaseAcquiredThroughTaxWithholdingRestrictedStock
Namespace Prefix:	snbr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration