Description of Business (Policies)	3 Months Ended
Aug. 30, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The Condensed Consolidated Financial Statements have been prepared by MillerKnoll, Inc. in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. Management believes the disclosures made in this document are adequate with respect to interim reporting requirements. Unless otherwise noted or indicated by the context, all references to "MillerKnoll," "we," "our," "Company" and similar references are to MillerKnoll, Inc., its predecessors, and controlled subsidiaries. The accompanying unaudited Condensed Consolidated Financial Statements, taken as a whole, contain all adjustments that are of a normal recurring nature necessary to present fairly the financial position of the Company as of August 30, 2025. Operating results for the three months ended August 30, 2025, are not necessarily indicative of the results that may be expected for the year ending May 30, 2026 ("fiscal 2026"). These Condensed Consolidated Financial Statements should be read in conjunction with the financial statements and notes thereto included in the Company's Annual Report on Form 10-K for the year ended May 31, 2025 ("fiscal 2025").
Intercompany Transactions and Equity Method Investments	All intercompany transactions have been eliminated in the Condensed Consolidated Financial Statements. The financial statements of equity method investments are not consolidated.
Fiscal Period	The Company's fiscal year is the 52 or 53 week period ending on the Saturday closest to May 31. The fiscal year ending May 30, 2026 ("fiscal 2026") and the fiscal year ended May 31, 2025 ("fiscal 2025") both contain 52 weeks.
Cash and Cash Equivalents	Cash and Cash Equivalents Certain of the Company’s subsidiaries participate in a notional cash pooling arrangement to manage global liquidity requirements. As part of a master netting arrangement, the participants combine their cash balances in pooling accounts at the same financial institution with the ability to offset bank overdrafts of one participant against positive cash account balances held by another participant. Under the terms of the master netting arrangement, the financial institution has the right, ability, and intent to offset a positive balance in one account against an overdrawn amount in another account. Amounts in each of the accounts are unencumbered and unrestricted with respect to use. As such, the net cash balance related to this pooling arrangement is included in Cash and cash equivalents in the accompanying Consolidated Balance Sheets.
Recently Adopted Accounting Standards and Recently Issued Accounting Standards Not Yet Adopted	The Company evaluates all Accounting Standards Updates ("ASUs") issued by the Financial Accounting Standards Board ("FASB") for consideration of their applicability to our consolidated financial statements. Recently Adopted Accounting Standards ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. In November 2023, the FASB issued this ASU to update reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses and information used to assess segment performance. The Company adopted ASU 2023-07 for the fiscal year ended May 31, 2025. We adopted this guidance on a retrospective basis, which modified our annual disclosures beginning in fiscal 2025 and our interim disclosures beginning in fiscal 2026 but did not have a material effect on the Company's financial position, results of operations, or cash flows. Refer to Note 13 Operating Segments in the accompanying notes to the consolidated statements for further detail. Recently Issued Accounting Standards Not Yet Adopted ASU 2023-09, Income Taxes (Topic 740): Improvements to Tax Disclosures. In December 2023, the FASB issued this ASU which expands disclosures in an entity’s income tax rate reconciliation table and regarding cash taxes paid both in the U.S. and foreign jurisdictions. The update will be effective for annual periods beginning after December 15, 2024. The Company expects the adoption of this guidance will modify our disclosures, but we do not expect it to have a material effect on our financial position, results of operations, or cash flows. ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses. In November 2024, the FASB issued this ASU which requires disclosure on an annual and interim basis, in the notes to the financial statements, of disaggregated information about specific categories underlying certain income statement expense line items. In January 2025, the FASB additionally issued ASU 2025-01, which clarified the effective date of ASU 2024-03 for entities that do not have a calendar year-end. The update will be effective in annual reporting periods beginning after December 15, 2026, and interim periods within annual reporting periods beginning after December 15, 2027, with early adoption permitted. The Company expects the adoption of this guidance will modify our disclosures, but we do not expect it to have a material effect on our financial position, results of operations, or cash flows. We have assessed all other ASUs issued but not yet adopted and concluded that those not disclosed are not relevant to the Company or are not expected to have a material impact.
Inventories	Inventories are valued primarily using the first-in first-out method.
Goodwill and Indefinite-Lived Intangibles	Goodwill Goodwill is tested for impairment at the reporting unit level annually, or more frequently when events or changes in circumstances indicate that the fair value of a reporting unit has more likely than not declined below its carrying value. When testing goodwill for impairment, the Company may first assess qualitative factors. If an initial qualitative assessment identifies that it is more likely than not that the carrying value of a reporting unit exceeds its estimated fair value, additional quantitative testing is performed. The Company may also elect to bypass the qualitative testing and proceed directly to the quantitative testing. If the quantitative testing indicates that goodwill is impaired, the carrying value of goodwill is written down to fair value.
Share-Based Compensation	Certain Company equity-based compensation awards contain provisions that allow for continued vesting into retirement. Stock-based awards are considered fully vested for expense attribution purposes when the employee's retention of the award is no longer contingent on providing subsequent service. Stock-based compensation expense is recorded within Selling, general and administrative expenses on the Condensed Consolidated Statements of Comprehensive Income (Loss).
Derivative Instruments and Hedging Activities	Derivative Instruments and Hedging Activities Foreign Currency Forward Contracts The Company transacts business in various foreign currencies and has established a program that primarily utilizes foreign currency forward contracts to offset the risks associated with the effects of certain foreign currency exposures. Under this program, the Company's strategy is to have increases or decreases in our foreign currency exposures offset by gains or losses on the foreign currency forward contracts to mitigate the risks and volatility associated with foreign currency transaction gains or losses. These foreign currency exposures typically arise from net liability or asset exposures in non-functional currencies on the balance sheets of our foreign subsidiaries. These foreign currency forward contracts generally settle within 30 days and are not used for trading purposes. These forward contracts are not designated as hedging instruments. Accordingly, we record the fair value of these contracts as of the end of the reporting period in the Consolidated Balance Sheets with changes in fair value recorded within the Consolidated Statements of Comprehensive Income. The balance sheet classification for the fair values of these forward contracts is Other current assets for unrealized gains and to Other accrued liabilities for unrealized losses. The Consolidated Statements of Comprehensive Income classification for the fair values of these forward contracts is to Other (income) expense, net, for both realized and unrealized gains and losses. Interest Rate Swaps The Company enters into interest rate swap agreements to manage its exposure to interest rate changes and its overall cost of borrowing. The Company's interest rate swap agreements exchange variable rate interest payments for fixed rate payments over the life of the agreement without the exchange of the underlying notional amounts. The notional amount of the interest rate swap agreements is used to measure interest to be paid or received. The differential paid or received on the interest rate swap agreements is recognized as an adjustment to interest expense.

Description of Business (Policies)

3 Months Ended

Aug. 30, 2025

Organization, Consolidation and Presentation of Financial Statements [Abstract]

The Condensed Consolidated Financial Statements have been prepared by MillerKnoll, Inc. in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. Management believes the disclosures made in this document are adequate with respect to interim reporting requirements. Unless otherwise noted or indicated by the context, all references to "MillerKnoll," "we," "our," "Company" and similar references are to MillerKnoll, Inc., its predecessors, and controlled subsidiaries.

The accompanying unaudited Condensed Consolidated Financial Statements, taken as a whole, contain all adjustments that are of a normal recurring nature necessary to present fairly the financial position of the Company as of August 30, 2025. Operating results for the three months ended August 30, 2025, are not necessarily indicative of the results that may be expected for the year ending May 30, 2026 ("fiscal 2026"). These Condensed Consolidated Financial Statements should be read in conjunction with the financial statements and notes thereto included in the Company's Annual Report on Form 10-K for the year ended May 31, 2025 ("fiscal 2025").

Intercompany Transactions and Equity Method Investments

All intercompany transactions have been eliminated in the Condensed Consolidated Financial Statements. The financial statements of equity method investments are not consolidated.

Fiscal Period

The Company's fiscal year is the 52 or 53 week period ending on the Saturday closest to May 31. The fiscal year ending May 30, 2026 ("fiscal 2026") and the fiscal year ended May 31, 2025 ("fiscal 2025") both contain 52 weeks.

Cash and Cash Equivalents

Certain of the Company’s subsidiaries participate in a notional cash pooling arrangement to manage global liquidity requirements. As part of a master netting arrangement, the participants combine their cash balances in pooling accounts at the same financial institution with the ability to offset bank overdrafts of one participant against positive cash account balances held by another participant. Under the terms of the master netting arrangement, the financial institution has the right, ability, and intent to offset a positive balance in one account against an overdrawn amount in another account. Amounts in each of the accounts are unencumbered and unrestricted with respect to use. As such, the net cash balance related to this pooling arrangement is included in Cash and cash equivalents in the accompanying Consolidated Balance Sheets.

Recently Adopted Accounting Standards and Recently Issued Accounting Standards Not Yet Adopted

The Company evaluates all Accounting Standards Updates ("ASUs") issued by the Financial Accounting Standards Board ("FASB") for consideration of their applicability to our consolidated financial statements.

Recently Adopted Accounting Standards

ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. In November 2023, the FASB issued this ASU to update reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses and information used to assess segment performance. The Company adopted ASU 2023-07 for the fiscal year ended May 31, 2025. We adopted this guidance on a retrospective basis, which modified our annual disclosures beginning in fiscal 2025 and our interim disclosures beginning in fiscal 2026 but did not have a material effect on the Company's financial position, results of operations, or cash flows. Refer to Note 13 Operating Segments in the accompanying notes to the consolidated statements for further detail.

Recently Issued Accounting Standards Not Yet Adopted

ASU 2023-09, Income Taxes (Topic 740): Improvements to Tax Disclosures. In December 2023, the FASB issued this ASU which expands disclosures in an entity’s income tax rate reconciliation table and regarding cash taxes paid both in the U.S. and foreign jurisdictions. The update will be effective for annual periods beginning after December 15, 2024. The Company expects the adoption of this guidance will modify our disclosures, but we do not expect it to have a material effect on our financial position, results of operations, or cash flows.

ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses. In November 2024, the FASB issued this ASU which requires disclosure on an annual and interim basis, in the notes to the financial statements, of disaggregated information about specific categories underlying certain income statement expense line items. In January 2025, the FASB additionally issued ASU 2025-01, which clarified the effective date of ASU 2024-03 for entities that do not have a calendar year-end. The update will be effective in annual reporting periods beginning after December 15, 2026, and interim periods within annual reporting periods beginning after December 15, 2027, with early adoption permitted. The Company expects the adoption of this guidance will modify our disclosures, but we do not expect it to have a material effect on our financial position, results of operations, or cash flows.

We have assessed all other ASUs issued but not yet adopted and concluded that those not disclosed are not relevant to the Company or are not expected to have a material impact.

Inventories

Inventories are valued primarily using the first-in first-out method.

Goodwill and Indefinite-Lived Intangibles

Goodwill

Goodwill is tested for impairment at the reporting unit level annually, or more frequently when events or changes in circumstances indicate that the fair value of a reporting unit has more likely than not declined below its carrying value. When testing goodwill for impairment, the Company may first assess qualitative factors. If an initial qualitative assessment identifies that it is more likely than not that the carrying value of a reporting unit exceeds its estimated fair value, additional quantitative testing is performed. The Company may also elect to bypass the qualitative testing and proceed directly to the quantitative testing. If the quantitative testing indicates that goodwill is impaired, the carrying value of goodwill is written down to fair value.

Share-Based Compensation

Certain Company equity-based compensation awards contain provisions that allow for continued vesting into retirement. Stock-based awards are considered fully vested for expense attribution purposes when the employee's retention of the award is no longer contingent on providing subsequent service. Stock-based compensation expense is recorded within Selling, general and administrative expenses on the Condensed Consolidated Statements of Comprehensive Income (Loss).

Derivative Instruments and Hedging Activities

Foreign Currency Forward Contracts

The Company transacts business in various foreign currencies and has established a program that primarily utilizes foreign currency forward contracts to offset the risks associated with the effects of certain foreign currency exposures. Under this program, the Company's strategy is to have increases or decreases in our foreign currency exposures offset by gains or losses on the foreign currency forward contracts to mitigate the risks and volatility associated with foreign currency transaction gains or losses. These foreign currency exposures typically arise from net liability or asset exposures in non-functional currencies on the balance sheets of our foreign subsidiaries. These foreign currency forward contracts generally settle within 30 days and are not used for trading purposes.

These forward contracts are not designated as hedging instruments. Accordingly, we record the fair value of these contracts as of the end of the reporting period in the Consolidated Balance Sheets with changes in fair value recorded within the Consolidated Statements of Comprehensive Income. The balance sheet classification for the fair values of these forward contracts is Other current assets for unrealized gains and to Other accrued liabilities for unrealized losses. The Consolidated Statements of Comprehensive Income classification for the fair values of these forward contracts is to Other (income) expense, net, for both realized and unrealized gains and losses.

Interest Rate Swaps

The Company enters into interest rate swap agreements to manage its exposure to interest rate changes and its overall cost of borrowing. The Company's interest rate swap agreements exchange variable rate interest payments for fixed rate payments over the life of the agreement without the exchange of the underlying notional amounts. The notional amount of the interest rate swap agreements is used to measure interest to be paid or received. The differential paid or received on the interest rate swap agreements is recognized as an adjustment to interest expense.