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Summary of Significant Accounting Policies - Additional Information (Details) $ in Millions			3 Months Ended		6 Months Ended
	May 01, 2025 retailLocation	Feb. 05, 2025 retailLocation	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($) channel	Jun. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Number of products sales channels | channel					2
Number of retail locations | retailLocation	73
Cost of sales			$ 1,053.6	$ 716.0	$ 2,077.8	$ 1,431.1
Revision of Prior Period, Adjustment
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Cost of sales				$ 36.7		$ 74.9
Accrued Expenses And Other Current Liabilities
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Standard product warranty accrual			24.0		24.0		$ 15.3
Other Noncurrent Liabilities
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Standard product warranty accrual			$ 35.6		$ 35.6		$ 18.3
Asia Pacific Joint Ventures
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Ownership percentage			50.00%		50.00%
United Kingdom Joint Venture
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Ownership percentage			50.00%		50.00%
Mattress Firm | Minimum
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Number of retail locations | retailLocation		2,200

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