Summary of Significant Accounting Policies (Policies)	9 Months Ended
Sep. 30, 2025
Accounting Policies [Abstract]
Basis of Presentation and Description of Business	Basis of Presentation and Description of Business. Somnigroup International Inc., a Delaware corporation, together with its subsidiaries, is a U.S. based, multinational company. The term "Somnigroup" refers to Somnigroup International Inc. only, and the term "Company" refers to Somnigroup International Inc. and its consolidated subsidiaries. Certain prior period amounts have been reclassified in the accompanying consolidated financial statements and notes thereto to conform to the current period presentation. The Company designs, manufactures, distributes and retails bedding products, which include mattresses, foundations and adjustable bases, and other products, which include pillows and other accessories. The Company also derives income from royalties by licensing Sealy® and Stearns & Foster® brands, technology and trademarks to other manufacturers. The Company sells its products through two sales channels: Wholesale and Direct. On February 5, 2025, the Company completed the previously announced acquisition of Mattress Firm, the largest mattress specialty retailer in the U.S. Mattress Firm was founded in 1986 and operates over 2,200 brick and mortar retail locations and a growing e-commerce platform. Mattress Firm's highly trained retail sales associates provide personalized service to help consumers choose the ideal bedding products across their robust assortment of market-leading brands.
Basis of Consolidation	The Company has ownership interests in Asia-Pacific joint ventures to develop markets for Sealy® and Stearns & Foster® branded products and ownership in a United Kingdom joint venture to manufacture, market and distribute Sealy® and Stearns & Foster® branded products. The Company's ownership interests in each of these joint ventures is 50.0%. The equity method of accounting is used for these joint ventures, over which the Company has significant influence but does not have control, and consolidation is not otherwise required. The Company's equity in the net income and losses of these investments is reported in equity income in earnings of unconsolidated affiliates in the accompanying Condensed Consolidated Statements of Income. The accompanying unaudited Condensed Consolidated Financial Statements have been prepared in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X and include all of the information and disclosures required by generally accepted accounting principles in the United States ("GAAP") for interim financial reporting. These unaudited Condensed Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements of the Company and related footnotes for the year ended December 31, 2024, included in the 2024 Annual Report filed with the Securities and Exchange Commission on February 28, 2025. The results of operations for the interim periods are not necessarily indicative of results of operations for a full year. It is the opinion of management that all necessary adjustments for a fair presentation of the results of operations for the interim periods have been made and are of a recurring nature unless otherwise disclosed herein.
Cash, Cash Equivalents and Restricted Cash	Cash, Cash Equivalents and Restricted Cash. Cash and cash equivalents consist of all highly liquid investments with initial maturities of three months or less. The carrying value of cash and cash equivalents approximates fair value because of the short-term maturity of those instruments. Restricted cash consists of proceeds from the Term B Loan which were funded into escrow as of December 31, 2024 and released upon the closing of the Mattress Firm Acquisition on February 5, 2025. The carrying value of restricted cash approximates fair value because of the short-term maturity of those instruments.
Inventories	Inventories. Inventories are stated at the lower of cost or net realizable value, determined by either the first-in, first-out method or the weighted average cost method, depending on reportable segment
Warranties	Warranties. The Company provides product warranties on both manufactured and sourced products and service warranties, which vary by segment, product and brand. Estimates of warranty expenses are based primarily on historical claims experience, product testing and recent trends. Estimated future obligations related to these products are charged to cost of sales in the period in which the related revenue is recognized. The Company considers the impact of recoverable salvage value on warranty costs in determining its estimate of future warranty obligations.
Allowance for Credit Losses	Allowance for Credit Losses. The allowance for credit losses is the Company's best estimate of the amount of expected lifetime credit losses in the Company's accounts receivable. The Company regularly reviews the adequacy of its allowance for credit losses. The Company estimates losses over the contractual life using assumptions to capture the risk of loss, even if remote, based principally on how long a receivable has been outstanding. As of September 30, 2025, the Company's accounts receivable were substantially current. Account balances are charged off against the allowance for credit losses after all reasonable means of collection have been exhausted and the potential for recovery is considered remote. Other factors considered include historical write-off experience, current economic conditions and also factors such as customer credit, past transaction history with the customer and changes in customer payment terms. The allowance for credit losses is included in accounts receivable, net in the accompanying Condensed Consolidated Balance Sheets.
Fair Value	Fair Value. Financial instruments, although not recorded at fair value on a recurring basis, include cash and cash equivalents, accounts receivable, accounts payable and the Company's debt obligations. The carrying value of cash and cash equivalents, accounts receivable and accounts payable approximate fair value because of the short-term maturity of those instruments. Borrowings under the 2023 Credit Agreement (as defined in Note 5, "Debt") and the securitized debt are at variable interest rates and accordingly their carrying amounts approximate fair value. The fair value of the following material financial instruments were based on Level 2 inputs, which include observable inputs estimated using discounted cash flows and market-based expectations for interest rates, credit risk and the contractual terms of debt instruments.
Cost of Sales	Cost of Sales. Costs associated with net sales are recorded in cost of sales. Cost of sales includes the costs of receiving, producing, inspecting, warehousing, insuring and shipping goods during the period, as well as depreciation and amortization of long-lived assets used in these processes. Cost of sales also includes retail store occupancy costs such as rent, common area maintenance charges, real estate and other asset-based taxes, general maintenance, utilities, depreciation and certain insurance expenses. The Company believes the classification of occupancy costs could vary widely throughout the industry. Because of this, the Company's gross profit and gross profit as a percentage of net sales may not be comparable to others in the industry which may include occupancy costs in total operating expenses. Additionally, cost of sales include royalties that the Company pays to other entities for the use of their names on products produced by the Company. Royalty expense is not material to the Company's Condensed Consolidated Statements of Income.
Vendor Incentives	(h) Vendor Incentives. The Company's Mattress Firm business segment earns various types of incentives from its suppliers related to purchase volume rebates, sales, reimbursements of certain sales and marketing expenses, long-term supply agreements and other ordinary course transactions, collectively referred to as vendor incentives. Amounts earned for vendor incentives are recorded within accounts payable until realized and are not material to the Company's Condensed Consolidated Balance Sheets. Vendor incentives are generally recorded as a reduction of inventory at the time of purchase and, subsequently, as a reduction to cost of sales when the product is sold. Vendor incentives earned for long-term supply agreements are deferred and ratably recorded as a reduction to cost of sales over the life of the supply agreement. Vendor incentives which represent the reimbursement of certain sales and marketing expenses for the vendor's products are recorded as a reduction of sales and marketing expenses. Certain vendor incentives include product purchase estimates and assumptions which may result in subsequent period adjustments if actual results differ from the estimates and assumptions used at the time of recognition. Vendor incentives earned for expense reimbursements also include estimates for sales and marketing expenses incurred at the time of recognition. If vendor incentives exceed our sales and marketing expenses, the excess amount is recorded as a reduction to cost of sales. The Company regularly reviews the adequacy of its estimates and assumptions used in the recognition of vendor incentives.

Summary of Significant Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2025

Basis of Presentation and Description of Business

Basis of Presentation and Description of Business. Somnigroup International Inc., a Delaware corporation, together with its subsidiaries, is a U.S. based, multinational company. The term "Somnigroup" refers to Somnigroup International Inc. only, and the term "Company" refers to Somnigroup International Inc. and its consolidated subsidiaries. Certain prior period amounts have been reclassified in the accompanying consolidated financial statements and notes thereto to conform to the current period presentation.

The Company designs, manufactures, distributes and retails bedding products, which include mattresses, foundations and adjustable bases, and other products, which include pillows and other accessories. The Company also derives income from royalties by licensing Sealy® and Stearns & Foster® brands, technology and trademarks to other manufacturers. The Company sells its products through two sales channels: Wholesale and Direct.

On February 5, 2025, the Company completed the previously announced acquisition of Mattress Firm, the largest mattress specialty retailer in the U.S. Mattress Firm was founded in 1986 and operates over 2,200 brick and mortar retail locations and a growing e-commerce platform. Mattress Firm's highly trained retail sales associates provide personalized service to help consumers choose the ideal bedding products across their robust assortment of market-leading brands.

Basis of Consolidation

The Company has ownership interests in Asia-Pacific joint ventures to develop markets for Sealy® and Stearns & Foster® branded products and ownership in a United Kingdom joint venture to manufacture, market and distribute Sealy® and Stearns & Foster® branded products. The Company's ownership interests in each of these joint ventures is 50.0%. The equity method of accounting is used for these joint ventures, over which the Company has significant influence but does not have control, and consolidation is not otherwise required. The Company's equity in the net income and losses of these investments is reported in equity income in earnings of unconsolidated affiliates in the accompanying Condensed Consolidated Statements of Income.

The accompanying unaudited Condensed Consolidated Financial Statements have been prepared in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X and include all of the information and disclosures required by generally accepted accounting principles in the United States ("GAAP") for interim financial reporting. These unaudited Condensed Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements of the Company and related footnotes for the year ended December 31, 2024, included in the 2024 Annual Report filed with the Securities and Exchange Commission on February 28, 2025.

The results of operations for the interim periods are not necessarily indicative of results of operations for a full year. It is the opinion of management that all necessary adjustments for a fair presentation of the results of operations for the interim periods have been made and are of a recurring nature unless otherwise disclosed herein.

Cash, Cash Equivalents and Restricted Cash

Cash, Cash Equivalents and Restricted Cash. Cash and cash equivalents consist of all highly liquid investments with initial maturities of three months or less. The carrying value of cash and cash equivalents approximates fair value because of the short-term maturity of those instruments. Restricted cash consists of proceeds from the Term B Loan which were funded into escrow as of December 31, 2024 and released upon the closing of the Mattress Firm Acquisition on February 5, 2025. The carrying value of restricted cash approximates fair value because of the short-term maturity of those instruments.

Inventories

Inventories. Inventories are stated at the lower of cost or net realizable value, determined by either the first-in, first-out method or the weighted average cost method, depending on reportable segment

Warranties

Warranties. The Company provides product warranties on both manufactured and sourced products and service warranties, which vary by segment, product and brand. Estimates of warranty expenses are based primarily on historical claims experience, product testing and recent trends. Estimated future obligations related to these products are charged to cost of sales in the period in which the related revenue is recognized. The Company considers the impact of recoverable salvage value on warranty costs in determining its estimate of future warranty obligations.

Allowance for Credit Losses

Allowance for Credit Losses. The allowance for credit losses is the Company's best estimate of the amount of expected lifetime credit losses in the Company's accounts receivable. The Company regularly reviews the adequacy of its allowance for credit losses. The Company estimates losses over the contractual life using assumptions to capture the risk of loss, even if remote, based principally on how long a receivable has been outstanding. As of September 30, 2025, the Company's accounts receivable were substantially current. Account balances are charged off against the allowance for credit losses after all reasonable means of collection have been exhausted and the potential for recovery is considered remote. Other factors considered include historical write-off experience, current economic conditions and also factors such as customer credit, past transaction history with the customer and changes in customer payment terms. The allowance for credit losses is included in accounts receivable, net in the accompanying Condensed Consolidated Balance Sheets.

Fair Value

Fair Value. Financial instruments, although not recorded at fair value on a recurring basis, include cash and cash equivalents, accounts receivable, accounts payable and the Company's debt obligations. The carrying value of cash and cash equivalents, accounts receivable and accounts payable approximate fair value because of the short-term maturity of those instruments. Borrowings under the 2023 Credit Agreement (as defined in Note 5, "Debt") and the securitized debt are at variable interest rates and accordingly their carrying amounts approximate fair value. The fair value of the following material financial instruments were based on Level 2 inputs, which include observable inputs estimated using discounted cash flows and market-based expectations for interest rates, credit risk and the contractual terms of debt instruments.

Cost of Sales

Cost of Sales. Costs associated with net sales are recorded in cost of sales. Cost of sales includes the costs of receiving, producing, inspecting, warehousing, insuring and shipping goods during the period, as well as depreciation and amortization of long-lived assets used in these processes. Cost of sales also includes retail store occupancy costs such as rent, common area maintenance charges, real estate and other asset-based taxes, general maintenance, utilities, depreciation and certain insurance expenses. The Company believes the classification of occupancy costs could vary widely throughout the industry. Because of this, the Company's gross profit and gross profit as a percentage of net sales may not be comparable to others in the industry which may include occupancy costs in total operating expenses.

Additionally, cost of sales include royalties that the Company pays to other entities for the use of their names on products produced by the Company. Royalty expense is not material to the Company's Condensed Consolidated Statements of Income.

Vendor Incentives

(h) Vendor Incentives. The Company's Mattress Firm business segment earns various types of incentives from its suppliers related to purchase volume rebates, sales, reimbursements of certain sales and marketing expenses, long-term supply agreements and other ordinary course transactions, collectively referred to as vendor incentives. Amounts earned for vendor incentives are recorded within accounts payable until realized and are not material to the Company's Condensed Consolidated Balance Sheets.

Vendor incentives are generally recorded as a reduction of inventory at the time of purchase and, subsequently, as a reduction to cost of sales when the product is sold. Vendor incentives earned for long-term supply agreements are deferred and ratably recorded as a reduction to cost of sales over the life of the supply agreement. Vendor incentives which represent the reimbursement of certain sales and marketing expenses for the vendor's products are recorded as a reduction of sales and marketing expenses.

Certain vendor incentives include product purchase estimates and assumptions which may result in subsequent period adjustments if actual results differ from the estimates and assumptions used at the time of recognition. Vendor incentives earned for expense reimbursements also include estimates for sales and marketing expenses incurred at the time of recognition. If vendor incentives exceed our sales and marketing expenses, the excess amount is recorded as a reduction to cost of sales. The Company regularly reviews the adequacy of its estimates and assumptions used in the recognition of vendor incentives.