MillerKnoll (MLKN) 10-Q 8 Apr 15 2015 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Feb. 28, 2015	Apr. 06, 2015
Document Entity Information [Abstract]
Entity Registrant Name	MILLER HERMAN INC
Entity Central Index Key	66382
Document Type	10-Q
Document Period End Date	28-Feb-15
Amendment Flag	FALSE
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	-25
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		59,654,160

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $)	3 Months Ended		9 Months Ended
In Millions, except Per Share data, unless otherwise specified	Feb. 28, 2015	Mar. 01, 2014	Feb. 28, 2015	Mar. 01, 2014
Income Statement [Abstract]
Net sales	$516.40	$455.90	$1,591.50	$1,394.50
Cost of sales	325.9	293	1,009.70	942.7
Gross margin	190.5	162.9	581.8	451.8
Operating expenses:
Selling, general, and administrative	133	111.7	400.8	449.6
Restructuring and impairment expenses	1.9	1.1	1.9	5.1
Design and research	18.2	16	52.8	49
Total operating expenses	153.1	128.8	455.5	503.7
Operating earnings (loss)	37.4	34.1	126.3	-51.9
Other expenses:
Interest expense	4.4	4.5	13.7	13.3
Other, net	1	0.3	1.1	0.3
Earnings (loss) before income taxes and equity income	32	29.3	111.5	-65.5
Income tax expense (benefit)	10.8	9.8	37.3	-26.9
Equity earnings (loss) from nonconsolidated affiliates, net of tax	0	-0.1	0.1	-0.1
Net earnings (loss)	21.2	19.4	74.3	-38.7
Net earnings attributable to noncontrolling interests	0.2	0	0.2	0
Net earnings (loss) attributable to Herman Miller, Inc.	21	19.4	74.1	-38.7
Earnings (loss) per share — basic	$0.35	$0.33	$1.25	($0.66)
Earnings (loss) per share — diluted	$0.35	$0.33	$1.23	($0.66)
Dividends declared, per share	$0.14	$0.14	$0.42	$0.39
Other comprehensive income, net of tax
Foreign currency translation adjustments	-3.6	0.1	-9.5	2.2
Pension and post-retirement liability adjustments	0.3	0.3	1.2	87.9
Other comprehensive income (loss)	-3.3	0.4	-8.3	90.1
Comprehensive income	17.9	19.8	66	51.4
Comprehensive income attributable to noncontrolling interests	0.2	0	0.2	0
Comprehensive income attributable to Herman Miller, Inc.	$17.70	$19.80	$65.80	$51.40

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (Unaudited) (USD $)	Feb. 28, 2015	31-May-14
In Millions, unless otherwise specified
Current Assets:
Cash and cash equivalents	$61.80	$101.50
Marketable securities	6.4	11.1
Accounts and notes receivable, net	184.8	204.3
Inventories, net	128.5	78.4
Prepaid expenses and other	78	56.5
Total current assets	459.5	451.8
Property and equipment, at cost	849.6	789.2
Less — accumulated depreciation	-614.7	-594
Net property and equipment	234.9	195.2
Goodwill	303.7	228.2
Indefinite-lived intangibles	96	40.9
Other amortizable intangibles, net	54.3	44.2
Other noncurrent assets	44.4	30.6
Total Assets	1,192.80	990.9
Current Liabilities:
Current maturities of long-term debt	0	50
Accounts payable	141.8	136.9
Accrued compensation and benefits	67.4	65
Accrued warranty	26.1	25.2
Other accrued liabilities	90.2	79
Total current liabilities	325.5	356.1
Long-term debt	326	200
Pension and post-retirement benefits	16	18.2
Other liabilities	73.3	44.5
Total Liabilities	740.8	618.8
Redeemable noncontrolling interests	27.7	0
Stockholders' Equity:
Preferred stock, no par value (10,000,000 shares authorized, none issued)	0	0
Common stock, $0.20 par value (240,000,000 shares authorized)	11.9	11.9
Additional paid-in capital	133.5	122.4
Retained earnings	326.3	277.4
Accumulated other comprehensive loss	-46.2	-37.9
Key executive deferred compensation plans	-1.2	-1.7
Total Stockholder's Equity	424.3	372.1
Total Liabilities, Redeemable Noncontrolling Interests, and Stockholders' Equity	$1,192.80	$990.90

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Parentheticals) (USD $)	Feb. 28, 2015	31-May-14
Statement of Financial Position [Abstract]
Preferred stock Value	$0	$0
Preferred stock Shares Authorized	10,000,000	10,000,000
Preferred stock Shares Issued	0	0
Common Stock Par Value	$0.20	$0.20
Common stock Shares Authorized	240,000,000	240,000,000

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Feb. 28, 2015	Mar. 01, 2014
Statement of Cash Flows [Abstract]
Net earnings (loss)	$74.30	($38.70)
Adjustments to reconcile net earnings (loss) to net cash provided by operating activities:
Depreciation and amortization	38.6	32.3
Stock-based compensation	8.1	8.3
Excess tax benefits from stock-based compensation	-0.7	-0.9
Pension and post-retirement expenses	0.7	116.4
Deferred taxes	-2.5	-46.4
Gain on sales of property and dealers	0	-0.2
Restructuring and impairment expenses	1.9	5.1
Other, net	0.7	0.8
(Increase) decrease in current assets	3.2	-20.4
Increase (decrease) in current liabilities	-13.6	3
Decrease in non-current liabilities	-0.9	-8.9
Net Cash Provided by Operating Activities	109.8	50.4
Cash Flows from Investing Activities:
Proceeds from sales of property and dealers	0.3	0.2
Marketable securities purchases	0	-4.6
Marketable securities sales	4.6	4.3
Acquisitions, net of cash received	-154	-6.7
Capital expenditures	-43.2	-32
Other, net	-8.2	-0.1
Net Cash Used in Investing Activities	-200.5	-38.9
Cash Flows from Financing Activities:
Dividends paid	-24.9	-22.1
Proceeds from issuance of long-term debt	622	0
Payments of long-term debt	-546	0
Common stock issued	7.2	10
Common stock repurchased and retired	-3.3	-4.3
Excess tax benefits from stock-based compensation	0.7	0.9
Payment of contingent consideration obligation	0	-1.3
Purchase of noncontrolling interests	-5.8	0
Other, net	0.8	0.2
Net Cash Provided by (Used in) Financing Activities	50.7	-16.6
Effect of Exchange Rate Changes on Cash and Cash Equivalents	0.3	-0.5
Net Increase (Decrease) in Cash and Cash Equivalents	-39.7	-5.6
Cash and Cash Equivalents, Beginning of Period	101.5	82.7
Cash and Cash Equivalents, End of Period	$61.80	$77.10

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) (USD $)	Total	Preferred Stock	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Key Executive Deferred Compensation	Noncontrolling Interests
In Millions, except Per Share data, unless otherwise specified
Balance at beginning of year at Jun. 01, 2013		$0	$11.70	$102.90	$331.10	($124.30)	($1.90)	$0
Balance at beginning of year at Jun. 01, 2013	0
Increase (Decrease) in Redeemable Noncontrolling Interest [Roll Forward]
Redeemable noncontrolling interests related to DWR acquisition	0
Stock-based compensation expense	0
Sale of redeemable noncontrolling interests	0
Stock options exercised	0
Net income attributable to redeemable noncontrolling interests	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchase and retirement of common stock				-4.2
Exercise of stock options			0.1	8.5
Stock-based compensation expense				8.3
Excess tax benefit for stock-based compensation				0.7
Restricted stock units released				0.2
Employee stock purchase plan issuances				1.1
Deferred compensation plan				-0.3
Directors' fees				0.3
Net income attributable to Herman Miller, Inc.	-38.7				-38.7
Dividends declared, per share	$0.39
Dividends declared on common stock (per share - 2015: $0.420; 2014; $0.390)					-23.2
Other comprehensive income (loss)	90.1					90.1
Deferred compensation plan							0.2
Noncontrolling interests related to DWR acquisition								0
Purchase of noncontrolling interests								0
Balance at end of period at Mar. 01, 2014	362.6	0	11.8	117.5	269.2	-34.2	-1.7	0
Redeemable noncontrolling interests at Mar. 01, 2014	0
Balance at beginning of year at May. 31, 2014		0	11.9	122.4	277.4	-37.9	-1.7	0
Balance at beginning of year at May. 31, 2014	0
Increase (Decrease) in Redeemable Noncontrolling Interest [Roll Forward]
Redeemable noncontrolling interests related to DWR acquisition	25.7
Stock-based compensation expense	0.9
Sale of redeemable noncontrolling interests	0.1
Stock options exercised	0.8
Net income attributable to redeemable noncontrolling interests	0.2
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchase and retirement of common stock				-3.3
Exercise of stock options			0	5.6
Stock-based compensation expense				7.2
Excess tax benefit for stock-based compensation				0.3
Restricted stock units released				0.2
Employee stock purchase plan issuances				1.2
Deferred compensation plan				-0.5
Directors' fees				0.4
Net income attributable to Herman Miller, Inc.	74.1				74.1
Dividends declared, per share	$0.42
Dividends declared on common stock (per share - 2015: $0.420; 2014; $0.390)					-25.2
Other comprehensive income (loss)	-8.3					-8.3
Deferred compensation plan							0.5
Noncontrolling interests related to DWR acquisition								5.8
Purchase of noncontrolling interests								-5.8
Balance at end of period at Feb. 28, 2015	424.3	0	11.9	133.5	326.3	-46.2	-1.2	0
Redeemable noncontrolling interests at Feb. 28, 2015	$27.70

Basis_of_Presentation

Basis of Presentation	9 Months Ended
	Feb. 28, 2015
Accounting Policies [Abstract]
Organization, Consolidation and Presentation of Financial Statements Disclosure	BASIS OF PRESENTATION
	The condensed consolidated financial statements have been prepared by Herman Miller, Inc. (“the company”) 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 accounting principles generally accepted in the United States of America for complete financial statements. Management believes the disclosures made in this document are adequate with respect to interim reporting requirements.
	The accompanying unaudited condensed consolidated financial statements, taken as a whole, contain all adjustments which are of a normal recurring nature necessary to present fairly the financial position of the company as of February 28, 2015. Operating results for the nine months ended February 28, 2015, are not necessarily indicative of the results that may be expected for the year ending May 30, 2015. It is suggested that these condensed consolidated financial statements be read in conjunction with the financial statements and notes thereto included in the company's Form 10-K filing for the year ended May 31, 2014.

New_Accounting_Standards

New Accounting Standards	9 Months Ended
	Feb. 28, 2015
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
New Accounting Pronouncements and Changes in Accounting Principles	NEW ACCOUNTING STANDARDS
	Recently Adopted Accounting Guidance
	During the first quarter of fiscal 2015, the company adopted Accounting Standards Update ("ASU") 2013-11, "Income Taxes (Topic 740): Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists," which defines the presentation requirements of an unrecognized tax benefit, or a portion of an unrecognized tax benefit, in the financial statements. The adoption of this standard did not have a material impact on the consolidated financial statements.
	Accounting Guidance Issued But Not Adopted as of February 28, 2015
	During the first quarter of fiscal 2015, the Financial Accounting Standards Board ("FASB") issued ASU 2014-12, "Compensation - Stock Compensation (Topic 718): Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could be Achieved after the Requisite Service Period." This ASU provides more specificity regarding the treatment of share-based payment awards that require a specific performance target that affects vesting and that could be achieved after the requisite service period as a performance condition. This guidance is effective for annual and interim reporting periods beginning after December 15, 2015. The adoption of this standard is not expected to have a material impact on the consolidated financial statements.
	In May 2014, the FASB issued ASU 2014-09, "Revenue from Contracts with Customers (Topic 606)," which is the single, comprehensive revenue recognition standard that will supersede all existing revenue recognition guidance under U.S. GAAP. The core principle of the standard is that a company will recognize revenue when it transfers promised goods or services to a customer in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services. This ASU is effective for annual and interim periods beginning on or after December 15, 2016. In April 2015, the FASB decided to defer the effective date of the new revenue standard by one year, resulting in the revenue standard being effective for annual reporting periods beginning after December 15, 2017. Under the proposal, companies would be permitted to early adopt the ASU as of the original effective date (annual periods beginning after December 15, 2016). The proposal to defer will be voted upon after the comment period has concluded. The company is currently evaluating the impact of adopting this guidance.

Fiscal_Year

Fiscal Year	9 Months Ended
	Feb. 28, 2015
Fiscal Year [Abstract]
Fiscal Year	FISCAL YEAR
	The company's fiscal year ends on the Saturday closest to May 31. Fiscal 2015, the year ending May 30, 2015, and fiscal 2014, the year ended May 31, 2014, each contain 52 weeks. The third quarters of fiscal 2015 and fiscal 2014 each contained 13 weeks.

Acquisitions_and_Divestitures

Acquisitions and Divestitures	9 Months Ended
	Feb. 28, 2015
Business Combinations [Abstract]
Acquisitions and Divestitures	ACQUISITIONS AND DIVESTITURES
	Design Within Reach Acquisition
	On July 28, 2014, the company acquired the majority of the outstanding equity of Design Within Reach, Inc. ("DWR"), a Stamford, Connecticut based, leading North American marketer and seller of modern furniture, lighting, and accessories primarily serving consumers and design trade professionals. The acquisition of DWR advances the company's strategy of being both an industry brand and a consumer brand by expanding the company's reach into the consumer sector.
	The company purchased an ownership interest in DWR equal to approximately 81 percent for $155.2 million in cash. The acquisition was financed by using a combination of existing cash and $127.0 million of borrowings on the company's available, unsecured credit facility. As a result of the transaction, the company estimates it will receive future tax benefits with a present value of approximately $10 million measured as of the date of acquisition. Additionally, certain senior management of DWR received fully-vested stock options, with a value of $1.7 million, in the equity of a newly-formed consumer-facing subsidiary that DWR merged into as a result of the transaction. These fully-vested equity awards are recorded in the Condensed Consolidated Balance Sheet within "Redeemable noncontrolling interests".
	Subsequent to the initial transaction, the company acquired an additional 4 percent of DWR stock from the remaining public shareholders for approximately $5.8 million in cash, all of which was paid during the first and second quarters of fiscal 2015. The remaining 15 percent of DWR stock was contributed by DWR executives into the newly formed consumer business subsidiary and the company contributed the assets of the existing Herman Miller Consumer business. After these transactions, the redeemable noncontrolling interests in the newly formed subsidiary, known as Herman Miller Consumer Holdings, Inc. ("HMCH"), was approximately 7 percent. The remaining HMCH shareholders have a put option to require the company to purchase their remaining interest over a five-year period from the date of issuance of such shares. As a result, these noncontrolling interests are not included within Stockholders' Equity within the Condensed Consolidated Balance Sheets, but rather are included within Redeemable noncontrolling interests.
	During the measurement period, the company made certain post-closing adjustments related to the final settlement of net working capital, valuation of customer relationship intangible assets, valuation of accounts receivable, and deferred income taxes that resulted in a net increase to goodwill of $1.8 million. The following table summarizes the fair values of the assets acquired and the liabilities assumed from the acquisition. The allocation of the purchase price is still considered preliminary, and the company is finalizing information related to the valuation and useful lives of intangible assets, deferred income taxes, and goodwill. The final determination of the fair values may result in further adjustments to the values presented below:
	Valuation as of July 28, 2014
	(In millions)	At acquisition date - reported as of August 30, 2014			Measurement Period Adjustments			At acquisition date - reported as of February 28, 2015
	Purchase price	$	155		$	0.2		$	155.2
	Fair value of the assets acquired:
	Cash	1.2			—			1.2
	Accounts receivable	2.4			(0.2		)	2.2
	Inventory	47.4			—			47.4
	Current deferred tax asset	—			1.7			1.7
	Other current assets	5.5			—			5.5
	Long term deferred tax asset	3.7			(3.7		)	—
	Goodwill	74.4			1.8			76.2
	Other intangible assets	69.6			(0.3		)	69.3
	Property	32			—			32
	Other long term assets	2.4			—			2.4
	Total assets acquired	238.6			(0.7		)	237.9
	Fair value of liabilities assumed:
	Accounts payable	20.8			—			20.8
	Current deferred tax liabilities	0.6			(0.6		)	—
	Accrued compensation and benefits	1.6			—			1.6
	Other accrued liabilities	12.3			(0.1		)	12.2
	Long term deferred tax liability	16.4			(0.2		)	16.2
	Other long term liabilities	0.4			—			0.4
	Total liabilities assumed	52.1			(0.9		)	51.2
	Redeemable noncontrolling interests	25.7			—			25.7
	Noncontrolling interests	5.8			—			5.8
	Net assets acquired	$	155		$	0.2		$	155.2
	The goodwill stemming from the transaction in the amount of $76.2 million was preliminarily recorded as "Goodwill" in the Condensed Consolidated Balance Sheet and allocated to the Consumer reportable segment. The goodwill recognized is attributable primarily to the assembled workforce and expected synergies from DWR and the total amount of this goodwill is not deductible for tax purposes.
	Other intangible assets acquired as a result of the acquisition of DWR were preliminarily valued at $69.3 million. These amounts are reflected in the values presented in the following table:
	Intangible Assets Acquired from the DWR Acquisition
	(In millions)	Fair Value			Useful Life
	Trade Names and Trademarks	$	55.1		Indefinite
	Exclusive Distribution Agreements	0.2			1.5 years
	Customer Relationships	12.8			10 - 16 years
	Product Development Designs	1.2			7 years
	Total Intangible Assets Acquired	$	69.3
	The following table provides net sales and results of operations from DWR included in the company’s results since the July 28, 2014 acquisition.
	DWR Results of Operations
		Three Months Ended			Nine Months Ended
	(In millions)	28-Feb-15			28-Feb-15
	DWR Net sales	$	59.5		$	147.9
	Intercompany sales elimination	(7.0		)	(14.4		)
	Net sales impact to Herman Miller, Inc.	$	52.5		$	133.5
	Net loss	$	(0.5	)	$	(4.3	)
	DWR acquisition-related expenses were $2.2 million for the nine-month period ended February 28, 2015. These expenses included legal and professional services fees.
	China Manufacturing and Distribution Acquisition
	On September 30, 2013, the company acquired certain assets from Dongguan Sun Hing Steel Furniture Factory Ltd (DGSH) which together constituted the acquisition of a business. The acquired business is a manufacturing and distribution operation in Dongguan, China. Consideration transferred to acquire the net assets of DGSH consisted of $8.2 million in cash, of which $6.7 million was paid during the second and third quarters of fiscal 2014. The remaining payment is recorded in the Condensed Consolidated Balance Sheets within "Other Accrued Liabilities" and is expected to be made within the next nine months. The company has finalized the purchase accounting for the acquisition of the China manufacturing and distribution facility.
	Divestitures
	During the third quarter of fiscal 2014, the company completed the sale of one wholly-owned contract furniture dealership in Montreal, Canada. The effect of this transaction on the company's consolidated financial statements was not material. The company also completed the sale of one wholly-owned contract furniture dealership in Oregon and one wholly-owned contract furniture dealership in Arkansas during the first quarter and second quarter of fiscal 2014, respectively. The effects of these transactions on the company's consolidated financial statements were also not material.

Inventories

Inventories	9 Months Ended
	Feb. 28, 2015
Inventories [Abstract]
Inventory Disclosure	INVENTORIES, NET
	(In millions)	28-Feb-15		31-May-14
	Finished goods	$	104.8	$	58.2
	Raw materials	23.7		20.2
	Total	$	128.5	$	78.4
	Inventories are valued at the lower of cost or market and include material, labor, and overhead. The inventories of the majority of domestic manufacturing subsidiaries are valued using the last-in, first-out method ("LIFO"). The inventories of all other subsidiaries are valued using the first-in, first-out method ("FIFO")

Goodwill_and_Indefinitelived_I

Goodwill and Indefinite-lived Intangibles	9 Months Ended
	Feb. 28, 2015
Goodwill and Indefinite-lived Intangibles [Abstract]
Goodwill and Intangible Assets Disclosure	GOODWILL AND INDEFINITE-LIVED INTANGIBLES
	Goodwill and other indefinite-lived intangible assets included in the Condensed Consolidated Balance Sheets consisted of the following as of February 28, 2015 and May 31, 2014:
	(In millions)	Goodwill			Indefinite-lived Intangible Assets		Total Goodwill and Indefinite-lived Intangible Assets
	May 31, 2014	$	228.2		$	40.9	$	269.1
	Foreign currency translation adjustments	(0.7		)	—		(0.7		)
	DWR acquisition	76.2			55.1		131.3
	February 28, 2015	$	303.7		$	96	$	399.7

Employee_Benefit_Plans

Employee Benefit Plans	9 Months Ended
	Feb. 28, 2015
Employee Benefit Plans [Abstract]
Pension and Other Postretirement Benefits Disclosure	EMPLOYEE BENEFIT PLANS
	Pension Plans and Post-Retirement Medical Insurance
	During the second quarter of fiscal 2014, the company settled the remaining obligations associated with its primary domestic defined benefit pension plans. Plan participants received vested benefits from the plan assets by electing a lump sum distribution, a roll-over contribution to other 401(k) or individual retirement plans, or an annuity contract with a qualifying third-party provider. These payments resulted in the settlement of the primary domestic defined benefit pension plans, thus relieving the company of any further obligation.
	Components of Net Periodic Benefit Costs
	(In millions)	Three Months Ended
		Pension Benefits						Other Post-Retirement Benefits
		February 28, 2015			March 1, 2014			February 28, 2015		March 1, 2014
	Domestic:
	Interest cost	$	—		$	—		$	0.1	$	0.1
	Expected return on plan assets	—			—			—		—
	Net amortization loss	—			—			—		—
	Settlement loss recognized	—			—			—		—
	Net periodic benefit cost	$	—		$	—		$	0.1	$	0.1
	International:
	Interest cost	$	1.2		$	1
	Expected return on plan assets	(1.5		)	(1.2		)
	Net amortization loss	0.5			0.4
	Net periodic benefit cost	$	0.2		$	0.2
		Nine Months Ended
		Pension Benefits						Other Post-Retirement Benefits
		February 28, 2015			March 1, 2014			February 28, 2015		March 1, 2014
	Domestic:
	Interest cost	$	—		$	5.2		$	0.2	$	0.2
	Expected return on plan assets	—			(3.8		)	—		—
	Net amortization loss	—			4.8			—		—
	Settlement loss recognized	—			158.2			—		—
	Net periodic benefit cost	$	—		$	164.4		$	0.2	$	0.2
	International:
	Interest cost	$	3.5		$	3
	Expected return on plan assets	(4.5		)	(3.6		)
	Net amortization loss	1.5			1.2
	Net periodic benefit cost	$	0.5		$	0.6

Earnings_Per_Share

Earnings Per Share	9 Months Ended
	Feb. 28, 2015
Earnings Per Share [Abstract]
Earnings Per Share	EARNINGS PER SHARE
	The following table reconciles the numerators and denominators used in the calculations of basic and diluted earnings per share (EPS).
		Three Months Ended				Nine Months Ended
		February 28, 2015		March 1, 2014		February 28, 2015		March 1, 2014
	Numerators:
	Numerator for both basic and diluted EPS, net earnings - in millions	$	21	$	19.4	$	74.1	$	(38.7	)
	Denominators:
	Denominator for basic EPS, weighted-average common shares outstanding	59,550,289		59,014,789		59,430,575		58,888,514
	Potentially dilutive shares resulting from stock plans	547,900		638,628		566,292		—
	Denominator for diluted EPS	60,098,189		59,653,417		59,996,867		58,888,514
	Antidilutive equity awards not included in weighted-average common shares - diluted	676,405		780,800		703,364		2,782,663
	The total antidilutive equity awards not included in the weighted-average common shares for the third quarters of fiscal 2015 and fiscal 2014 were 676,405 shares and 780,800 shares, respectively. Included within these amounts were options to purchase 676,405 shares and 765,448 shares, respectively.
	For the nine months ended February 28, 2015 and March 1, 2014, the total antidilutive equity shares not included in the weighted-average common shares were 703,364 shares and 2,782,663 shares, respectively. Included within these amounts were options to purchase 703,364 shares and 2,134,500 shares, respectively.
	The company has certain share-based payment awards that meet the definition of participating securities. The company has evaluated the impact on EPS of all participating securities under the two-class method, noting the impact on EPS was immaterial.

StockBased_Compensation

Stock-Based Compensation	9 Months Ended
	Feb. 28, 2015
Stock-Based Compensation [Abstract]
Stock-Based Compensation	STOCK-BASED COMPENSATION
	The company's stock-based compensation expense for the three month periods ended February 28, 2015 and March 1, 2014 was $2.4 million and $2.7 million, respectively. The related income tax effect for the three month periods ended February 28, 2015 and March 1, 2014 was $0.8 million and $1.0 million, respectively. For the nine months ended February 28, 2015 and March 1, 2014, compensation costs were $8.1 million and $8.3 million, respectively. The related income tax effect for the respective nine month periods was $2.9 million and $3.0 million, respectively.
	Stock-based compensation expense recognized in the Condensed Consolidated Statements of Comprehensive Income for the three and nine month periods ended February 28, 2015 and March 1, 2014 has been reduced for estimated forfeitures, as it is based on awards ultimately expected to vest. Forfeitures are estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ. Forfeitures are estimated based on historical experience.
	For the nine month period ended February 28, 2015, the company issued 258,927 shares of common stock related to the exercise of stock options and 130,144 of common stock related to the vesting of restricted stock units.
	For the nine month period ended March 1, 2014, the company issued 412,541 shares of common stock related to the exercise of stock options and 108,947 shares of common stock related to the vesting of restricted stock units.
	Stock Option Plans
	The company has stock option plans under which options to purchase the company's stock are granted to employees, directors, and consultants at a price not less than the market price of the company's common stock on the date of grant. Under the current award program, all options become exercisable between one year and three years from date of grant and expire ten years from date of grant. Most options are subject to graded vesting with the related compensation expense recognized on a straight-line basis over the requisite service period. The company estimates the issuance date fair value of stock options on the date of grant using the Black-Scholes model.
	Herman Miller Consumer Holdings Stock (HMCH) Option Plan
	Certain employees have been granted, as rollover grants from the acquisition of DWR, options to purchase stock of HMCH, a subsidiary of the company, at a price equal to the exercise price of the original DWR stock options. These awards are fully vested and exercisable at the rollover grant date, and expire at the end of the window period that follows the fifth anniversary of the grant date.
	Certain employees were also granted new options to purchase stock of HMCH at a price not less than the market price of HMCH common stock on the date of grant. For the grants of new options under the award program, options are potentially exercisable between one year and five years from date of grant and expire at the end of the window period that follows the fifth anniversary of the grant date. Vesting is based on the performance of HMCH over a period of five years. Compensation expense is determined based on grant-date fair value and the number of common shares of HMCH projected to be issued and is recognized over the requisite service period. The company estimates the issuance date fair value of HMCH stock options on the date of grant using the Black-Scholes model.
	Employee Stock Purchase Program
	Under the terms of the company's Employee Stock Purchase Plan, 4 million shares of authorized common stock were reserved for purchase by plan participants at 85 percent of the market price. The company recognizes pre-tax compensation expense related to the market value discount.
	Restricted Stock Grants
	The company periodically grants restricted common stock to certain key employees. Shares are granted in the name of the employee, who has all the rights of a shareholder, subject to certain restrictions on transferability and risk of forfeiture. The grants are subject to either cliff-based or graded vesting over a period not exceeding five years, and are subject to forfeiture if the employee ceases to be employed by the company for certain reasons. After the vesting period, the risk of forfeiture and restrictions on transferability lapse. The compensation expense for these awards is based on the closing stock price on the date of grant. The company recognizes the related compensation expense on a straight-line basis over the requisite service period.
	Restricted Stock Units
	The company grants restricted stock units to certain key employees. The awards generally cliff-vest after a three or five-year service period, with prorated vesting under certain circumstances and full or partial accelerated vesting upon retirement. Each restricted stock unit represents one equivalent share of the company's common stock to be issued, free of restrictions, after the vesting period. The compensation expense for these awards is based on the closing stock price on the date of grant. Compensation expense related to these awards is recognized over the requisite service period. Dividend equivalent awards are credited quarterly. The units do not entitle participants to the rights of shareholders of common stock, such as voting rights, until shares are issued after the vesting period.
	Performance Share Units
	The company has granted performance share units to certain key employees. Each unit represents one equivalent share of the company's common stock. The number of common shares ultimately issued in connection with these performance share units is determined based on the company's financial performance over the related three-year service period or the company's financial performance based on certain total shareholder return results as compared to a selected group of peer companies. Compensation expense is determined based on the grant-date fair value and the number of common shares projected to be issued and is recognized over the requisite service period.

Income_Taxes

Income Taxes	9 Months Ended
	Feb. 28, 2015
Income Tax Disclosure [Abstract]
Income Tax Disclosure	INCOME TAXES
	The effective tax rates for the three months ended February 28, 2015 and March 1, 2014, were 33.6 percent and 33.3 percent, respectively. The company's United States federal statutory rate is 35 percent. For the nine month periods ended February 28, 2015 and March 1, 2014, the effective tax rates were 33.5 percent and 41.1 percent, respectively. The decrease in the rate during the nine month period ended February 28, 2015 resulted from a shift in the relative mix of income and loss between the taxing jurisdictions from the prior year primarily due to legacy pension expenses recorded in the prior year.
	The company had income tax accruals associated with uncertain tax benefits totaling $1.5 million and $1.7 million as of February 28, 2015 and March 1, 2014, respectively.
	The company recognizes interest and penalties related to uncertain tax benefits through income tax expense in its Condensed Consolidated Statement of Comprehensive Income. Interest and penalties recognized in the company's Condensed Consolidated Statement of Comprehensive Income were $0.2 million for the three month period and $0.3 million for the nine month period ended February 28, 2015. Interest and penalties recognized in the company's Condensed Consolidated Statement of Comprehensive Income were negligible for the three and nine month periods ended March 1, 2014. The company's recorded liability for potential interest and penalties related to uncertain tax benefits totaled $0.9 million and $0.7 million as of February 28, 2015 and March 1, 2014, respectively.
	The company is subject to periodic audits by domestic and foreign tax authorities. Currently, the company is undergoing routine periodic audits in both domestic and foreign tax jurisdictions. It is reasonably possible that the amounts of unrecognized tax benefits could change in the next twelve months as a result of the audits. Tax payments related to these audits, if any, are not expected to be material to the company's Condensed Consolidated Statements of Comprehensive Income.
	For the majority of tax jurisdictions, the company is no longer subject to state, local, or non-United States income tax examinations by tax authorities for fiscal years before 2011.

Fair_Value_Measurements

Fair Value Measurements	9 Months Ended
	Feb. 28, 2015
Fair Value Disclosures [Abstract]
Fair Value and Investment Information	FAIR VALUE MEASUREMENTS
	The following describes the methods the company uses to estimate the fair value of financial assets and liabilities, which have not significantly changed in the current period:
	Available-for-sale securities — The company's available-for-sale marketable securities primarily include mortgage-backed debt securities, government obligations and corporate debt securities and are recorded at fair value using quoted prices for similar securities.
	Deferred compensation plan — The company's deferred compensation plan primarily includes various domestic and international mutual funds that are recorded at fair value using quoted prices for similar securities.
	Foreign currency exchange contracts — The company's foreign currency exchange contracts are valued using an approach based on foreign currency exchange rates obtained from active markets. The estimated fair value of forward currency exchange contracts is based on month-end spot rates as adjusted by market-based current activity.
	The following tables set forth financial assets and liabilities measured at fair value in the Condensed Consolidated Balance Sheets and the respective pricing levels to which the fair value measurements are classified within the fair value hierarchy as of February 28, 2015 and May 31, 2014.
	(In millions)	Fair Value Measurements
		February 28, 2015		May 31, 2014
	Financial Assets	Quoted Prices with		Quoted Prices with
		Other Observable Inputs		Other Observable Inputs
		(Level 2)		(Level 2)
	Available-for-sale marketable securities:
	Asset-backed securities	$	0.3	$	0.4
	Corporate securities	0.7		1.2
	Government obligations	4.9		7.9
	Mortgage-backed securities	0.5		1.6
	Foreign currency forward contracts	0.6		0.2
	Deferred compensation plan	7.6		6.3
	Total	$	14.6	$	17.6
	Financial Liabilities
	Foreign currency forward contracts	$	0.5	$	0.1
	Total	$	0.5	$	0.1
	The company does not hold any level 3 investments. The following is a summary of the carrying and market values of the company's marketable securities as of the respective dates.
		February 28, 2015
	(In millions)	Cost		Unrealized		Unrealized		Market
				Gain		Loss		Value
	Asset-backed securities	$	0.3	$	—	$	—	$	0.3
	Corporate securities	0.7		—		—		0.7
	Government obligations	4.9		—		—		4.9
	Mortgage-backed securities	0.5		—		—		0.5
	Total	$	6.4	$	—	$	—	$	6.4
		May 31, 2014
	(In millions)	Cost		Unrealized		Unrealized		Market
				Gain		Loss		Value
	Asset-backed securities	$	0.4	$	—	$	—	$	0.4
	Corporate securities	1.2		—		—		1.2
	Government obligations	7.9		—		—		7.9
	Mortgage-backed securities	1.6		—		—		1.6
	Total	$	11.1	$	—	$	—	$	11.1
	Adjustments to the fair value of available-for-sale securities are recorded as increases or decreases, net of income taxes, within accumulated other comprehensive loss in stockholders’ equity. The cost of securities sold is based on the specific identification method; realized gains and losses resulting from such sales are included in the Condensed Consolidated Statements of Comprehensive Income within "Other, net".
	The company reviews its investment portfolio for any unrealized losses that would be deemed other-than-temporary and require the recognition of an impairment loss in earnings. If the cost of an investment exceeds its fair value, the company evaluates, among other factors, general market conditions, the duration and extent to which the fair value is less than its cost, the company's intent to hold the investment, and whether it is more likely than not that the company will be required to sell the investment before recovery of the cost basis. The company also considers the type of security, related industry and sector performance, and published investment ratings. Once a decline in fair value is determined to be other-than-temporary, an impairment charge is recorded and a new cost basis in the investment is established. If conditions within individual markets, industry segments, or macro-economic environments deteriorate, the company could incur future impairments.
	Maturities of debt securities included in marketable securities as of February 28, 2015, are as follows.
	(In millions)	Cost		Fair Value
	Due within one year	$	2.7	$	2.7
	Due after one year through five years	3.6		3.6
	Due after five years through ten years	—		—
	Due after more than ten years	0.1		0.1
	Total	$	6.4	$	6.4
	The company views its available-for-sale portfolio as available for use in its current operations. Accordingly, the investments are recorded within Current Assets within the Condensed Consolidated Balance Sheets.

Commitments_and_Contingencies

Commitments and Contingencies	9 Months Ended
	Feb. 28, 2015
Commitments and Contingencies Disclosure [Abstract]
Contingencies And Guarantees Disclosure	COMMITMENTS AND CONTINGENCIES
	Product Warranties
	The company provides warranty coverage to the end-user for parts and labor on products sold. The standard length of warranty is twelve years for the majority of products sold; however, this varies depending on the product classification. The company does not sell or otherwise issue warranties or warranty extensions as stand-alone products. Reserves have been established for the various costs associated with the company's warranty program and are included in the Condensed Consolidated Balance Sheets under “Accrued warranty.” General warranty reserves are based on historical claims experience and other currently available information. These reserves are adjusted once an issue is identified and the actual cost of correction becomes known or can be estimated.
	(In millions)	Three Months Ended						Nine Months Ended
		February 28, 2015			March 1, 2014			February 28, 2015			March 1, 2014
	Accrual Balance — beginning	$	26		$	24.8		$	25.2		$	24.8
	Accrual for warranty matters	5.4			5.1			18.1			15.4
	Settlements and adjustments	(5.3		)	(4.5		)	(17.2		)	(14.8		)
	Accrual Balance — ending	$	26.1		$	25.4		$	26.1		$	25.4
	Guarantees
	The company is periodically required to provide performance bonds in order to do business with certain customers. These arrangements are common and generally have terms ranging between one and three years. The bonds are required to provide assurance to customers that the products and services they have purchased will be installed and/or provided properly and without damage to their facilities. The bonds are provided by various bonding agencies; however, the company is ultimately liable for claims that may occur against them. As of February 28, 2015, the company had a maximum financial exposure related to performance bonds totaling approximately $9.1 million. The company has no history of claims, nor is it aware of circumstances that would require it to pay, under any of these arrangements. The company also believes that the resolution of any claims that might arise in the future, either individually or in the aggregate, would not materially affect the company's financial statements. Accordingly, no liability has been recorded in respect to these bonds as of February 28, 2015 and May 31, 2014.
	The company has entered into standby letter of credit arrangements for purposes of protecting various insurance companies and lessors against default on insurance premium and lease payments. As of February 28, 2015, the company had a maximum financial exposure from these standby letters of credit totaling approximately $8.3 million, all of which is considered usage against the company's revolving credit facility. The company has no history of claims, nor is it aware of circumstances that would require it to perform under any of these arrangements, and believes that the resolution of any claims that might arise in the future, either individually or in the aggregate, would not materially affect the company's financial statements. Accordingly, no liability has been recorded in respect of these arrangements as of February 28, 2015 and May 31, 2014.
	Contingencies
	The company leases a facility in the United Kingdom under an agreement that expired in June 2011, and the company is currently leasing the facility on a month-to-month basis. Under the terms of the lease, the company is required to perform the maintenance and repairs necessary to address the general dilapidation of the facility. The ultimate cost of this provision to the company is dependent on a number of factors including, but not limited to, the future use of the facility by the lessor and whether the company chooses and is permitted to renew the lease term. The company has estimated the cost of these maintenance and repairs to be between $0 million and $3.0 million, depending on the outcome of future plans and negotiations. As a result, an estimated liability of $1.2 million and $1.5 million was recorded under the caption “Other accrued liabilities” in the Condensed Consolidated Balance Sheets as of February 28, 2015, and May 31, 2014, respectively.
	The company is also involved in legal proceedings and litigation arising in the ordinary course of business. In the opinion of management, the outcome of such proceedings and litigation currently pending will not materially affect the company's consolidated financial statements.

Debt

Debt	9 Months Ended
	Feb. 28, 2015
Debt Disclosure [Abstract]
Debt Disclosure	DEBT
	On January 3, 2015, $50.0 million of the company’s Series A senior notes became due and payable. This debt was paid through the use of borrowings on the company’s revolving line of credit.
	On July 21, 2014, the company entered into a third amendment and restatement of its syndicated revolving line of credit, which provides the company with up to $250 million in revolving variable interest borrowing capacity and includes an "accordion feature" allowing the company to increase, at its option and subject to the approval of the participating banks, the aggregate borrowing capacity of the facility by $125 million. The facility expires in July 2019 and outstanding borrowings bear interest at rates based on the prime rate, federal funds rate, LIBOR, or negotiated rates as outlined in the agreement. Interest is payable periodically throughout the period if borrowings are outstanding. As of February 28, 2015, the total debt outstanding related to borrowings against this facility was $126.0 million. These borrowings are included within Long-term debt in the Condensed Consolidated Balance Sheet. As of that date, the total usage against the facility was $134.3 million, of which $8.3 million related to outstanding letters of credit.
	During the second quarter of fiscal 2014, the company entered into a revolving line of credit, which provides the company with approximately $5.0 million in revolving variable interest borrowing capacity. The company intends to utilize the revolver, which is denominated in Chinese Renminbi, to meet working capital cash flow needs at its South China operations. The uncommitted facility is subject to changes in bank approval and outstanding borrowings bear interest at rates based on a benchmark lending rate. As of February 28, 2015 and May 31, 2014, there were no borrowings against this facility.
	During the second quarter of fiscal 2013, the company entered into a revolving line of credit, which provides the company with approximately $5.0 million in revolving variable interest borrowing capacity. The company intends to utilize the revolver, which is denominated in Chinese Renminbi, to meet working capital cash flow needs at its Ningbo, China operations. The uncommitted facility is subject to changes in bank approval and outstanding borrowings bear interest at rates based on a benchmark lending rate. Each draw on the line of credit is subject to a maximum period of one year and corresponding interest is payable on the maturity date of each draw. As of February 28, 2015 and May 31, 2014, there were no borrowings against this facility.
	During the second quarter of fiscal 2012, the company entered into an amendment and restatement of the syndicated revolving line of credit, which provided the company with up to $150 million in revolving variable interest borrowing capacity and included an "accordion feature", which allowed the company to increase, at its option and subject to the approval of the participating banks, the aggregate borrowing capacity of the facility by $75 million. This facility was replaced by the third amendment and restatement that occurred on July 21, 2014. As of May 31, 2014, total usage against this facility was $4.9 million, all of which related to outstanding letters of credit.

Accumulated_Other_Comprehensiv

Accumulated Other Comprehensive Income (Loss)	9 Months Ended
	Feb. 28, 2015
Accumulated Other Comprehensive Income (Loss) [Abstract]
Comprehensive Income (Loss) Note	ACCUMULATED OTHER COMPREHENSIVE LOSS
	The following table provides an analysis of the changes in accumulated other comprehensive income (loss) for the nine months ended February 28, 2015 and March 1, 2014:
		Nine Months Ended
	(In millions)	February 28, 2015			March 1, 2014
	Cumulative translation adjustments at beginning of period	$	(11.1	)	$	(14.0	)
	Translation adjustments	(9.5		)	2.2
	Balance at end of period	(20.6		)	(11.8		)
	Pension and other post-retirement benefit plans at beginning of period	(26.8		)	(110.3		)
	Adjustments to pension and other post-retirement benefit plans	—			(2.0		)
	Reclassification to earnings - cost of sales (net of tax $0.0, $(15.9))	—			27.6
	Reclassification to earnings - operating expenses (net of tax $(0.3), $(35.7))	1.2			62.3
	Balance at end of period	(25.6		)	(22.4		)
	Total accumulated other comprehensive loss	$	(46.2	)	$	(34.2	)

Restructuring_and_Impairment_A

Restructuring and Impairment Activities	9 Months Ended
	Feb. 28, 2015
Restructuring and Related Activities [Abstract]
Restructuring and Related Activities Disclosure [Text Block]	RESTRUCTURING AND IMPAIRMENT ACTIVITIES
	During the third quarter of fiscal 2015 the company announced restructuring actions involving targeted workforce reductions within the North American segment. These actions resulted in the recognition of restructuring expenses related to severance and outplacement costs totaling $1.9 million during the quarter.
	During the third quarter of fiscal 2014 the company recognized restructuring expenses of $1.1 million. This restructuring charge was related to actions taken to improve the efficiency of the North American sales and distribution channel and Geiger manufacturing operations. These actions focused primarily on targeted workforce reductions.
	Due to the acquisition of a manufacturing and distribution operation in Dongguan, China in the second quarter of 2014, the company
	decided not to pursue the construction of a new manufacturing and distribution facility on property that it previously acquired in Ningbo,
	China. In connection with this decision, the company evaluated the fair value of this property and recorded an asset impairment of $4.0 million during the second quarter of fiscal 2014. This impairment charge was recorded to the "Restructuring and impairment expenses" line item within the Condensed Consolidated Statements of Comprehensive Income. The impairment charge is included within the "Corporate" category within the segment reporting.

Operating_Segments

Operating Segments	9 Months Ended
	Feb. 28, 2015
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
Segment Reporting Disclosure	OPERATING SEGMENTS
	Following the acquisition of DWR, we realigned the composition of our reportable segments to reflect the new operational and management divisions of the business. As a result, our previously defined "Specialty and Consumer" structure has been divided into two separate segments. The "Specialty" segment includes the operations associated with our Geiger, Maharam, and Herman Miller Collection business units. Under the new structure, the company's "Consumer" business segment includes the results of our combined North American consumer wholesale and retail business, including DWR. Prior year results have been revised to reflect this change. The North American and ELA segments were not affected by these changes.
	The company's reportable segments consist of North American Furniture Solutions, ELA ("EMEA, Latin America, and Asia Pacific") Furniture Solutions, Specialty, and Consumer. The North American Furniture Solutions reportable segment includes the operations associated with the design, manufacture, and sale of furniture products for work-related settings, including office, education, and healthcare environments, throughout the United States and Canada. ELA Furniture Solutions includes the operations associated with the design, manufacture, and sale of furniture products, primarily for work-related settings, in the EMEA, Latin America, and Asia-Pacific geographic regions. Specialty includes the operations associated with the design, manufacture, and sale of high-craft furniture products and textiles including Geiger wood products, Maharam textiles, and Herman Miller Collection products. The Consumer segment includes the operations associated with the sale of modern design furnishings and accessories to third party retail distributors, as well as direct to consumer sales through eCommerce and DWR studios.
	The company also reports a “Corporate” category consisting primarily of unallocated corporate expenses including restructuring, impairment, acquisition-related costs, and other unallocated corporate costs.
	The accounting policies of the reportable operating segments are the same as those of the company. Additionally, the company employs a methodology for allocating corporate costs and assets with the underlying objective of this methodology being to allocate corporate costs according to the relative usage of the underlying resources and to allocate corporate assets according to the relative expected benefit. The company has determined that allocation based on relative net sales is appropriate. The majority of corporate costs are allocated to the operating segments; however, certain costs generally considered the result of isolated business decisions are not subject to allocation and are evaluated separately from the rest of the regular ongoing business operations. For example, restructuring charges that are reflected in operating earnings are allocated to the “Corporate” category.
	The performance of the operating segments is evaluated by the company's management using various financial measures. The following is a summary of certain key financial measures for the respective fiscal periods indicated.
		Three Months Ended						Nine Months Ended
	(In millions)	February 28, 2015			March 1, 2014			February 28, 2015			March 1, 2014
	Net Sales:
	North American Furniture Solutions	$	296		$	293.9		$	932.4		$	909.2
	ELA Furniture Solutions	97.3			97.9			307			282.6
	Specialty	50.5			47.5			160.5			152.7
	Consumer	72.6			16.6			191.6			50
	Corporate	—			—			—			—
	Total	$	516.4		$	455.9		$	1,591.50		$	1,394.50
	Depreciation and Amortization:
	North American Furniture Solutions	$	7.2		$	7		$	21.4		$	20.8
	ELA Furniture Solutions	1.9			1.8			6.3			5.7
	Specialty	1.9			1.6			5.4			4.9
	Consumer	2.3			0.3			5.3			0.9
	Corporate	0.1			—			0.2			—
	Total	$	13.4		$	10.7		$	38.6		$	32.3
	Operating Earnings (Loss):
	North American Furniture Solutions	$	26.7		$	26.7		$	95.2		$	(58.3	)
	ELA Furniture Solutions	6.2			4.7			19.7			12.9
	Specialty	1.9			(0.2		)	7.6			(7.3		)
	Consumer	4.6			3.8			8.4			5.9
	Corporate	(2.0		)	(0.9		)	(4.6		)	(5.1		)
	Total	$	37.4		$	34.1		$	126.3		$	(51.9	)
	Capital Expenditures:
	North American Furniture Solutions	$	8		$	7.1		$	23.7		$	22.3
	ELA Furniture Solutions	7.3			3			13.6			5.6
	Specialty	0.6			1.9			2.8			4.1
	Consumer	0.6			—			3.1			—
	Corporate	—			—			—			—
	Total	$	16.5		$	12		$	43.2		$	32
	(In millions)	February 28, 2015			May 31, 2014
	Total Assets:
	North American Furniture Solutions	$	512.9		$	457
	ELA Furniture Solutions	236.2			244.8
	Specialty	154.1			157.7
	Consumer	221.4			18.8
	Corporate	68.2			112.6
	Total	$	1,192.80		$	990.9
	Total Goodwill:
	North American Furniture Solutions	$	135.8		$	135.8
	ELA Furniture Solutions	41.9			42.6
	Specialty	49.8			49.8
	Consumer	76.2			—
	Corporate	—			—
	Total	$	303.7		$	228.2

Subsequent_Event

Subsequent Event	9 Months Ended
	Feb. 28, 2015
Subsequent Event [Abstract]
Subsequent Event Disclosure	SUBSEQUENT EVENTS
	Sale of Land in Ningbo, China
	On March 12, 2015, the company entered into an agreement for the sale of land in Ningbo, China. For the third quarter of fiscal 2015, this land qualified to be classified as an Asset Held for Sale. Accordingly, during the third quarter of fiscal 2015 the land was written down to its fair value, less estimated selling expenses, to an amount of $4.2 million and is now classified as a current asset and has been included within "prepaid expenses and other" on the Consolidated Balance Sheet for the period ended February 28, 2015. Impairment recorded during the period was not material.

Inventories_Policies

Inventories (Policies)	9 Months Ended
	Feb. 28, 2015
Inventories [Abstract]
Inventory, Policy	Inventories are valued at the lower of cost or market and include material, labor, and overhead. The inventories of the majority of domestic manufacturing subsidiaries are valued using the last-in, first-out method ("LIFO"). The inventories of all other subsidiaries are valued using the first-in, first-out method ("FIFO")

Fair_Value_Measurements_Polici

Fair Value Measurements (Policies)	9 Months Ended
	Feb. 28, 2015
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments, Policy	Adjustments to the fair value of available-for-sale securities are recorded as increases or decreases, net of income taxes, within accumulated other comprehensive loss in stockholders’ equity. The cost of securities sold is based on the specific identification method; realized gains and losses resulting from such sales are included in the Condensed Consolidated Statements of Comprehensive Income within "Other, net".

Acquisitions_and_Divestitures_

Acquisitions and Divestitures (Tables)	9 Months Ended
	Feb. 28, 2015
Business Combinations [Abstract]
Schedule of Business Acquisitions, by Acquisition	The final determination of the fair values may result in further adjustments to the values presented below:
	Valuation as of July 28, 2014
	(In millions)	At acquisition date - reported as of August 30, 2014			Measurement Period Adjustments			At acquisition date - reported as of February 28, 2015
	Purchase price	$	155		$	0.2		$	155.2
	Fair value of the assets acquired:
	Cash	1.2			—			1.2
	Accounts receivable	2.4			(0.2		)	2.2
	Inventory	47.4			—			47.4
	Current deferred tax asset	—			1.7			1.7
	Other current assets	5.5			—			5.5
	Long term deferred tax asset	3.7			(3.7		)	—
	Goodwill	74.4			1.8			76.2
	Other intangible assets	69.6			(0.3		)	69.3
	Property	32			—			32
	Other long term assets	2.4			—			2.4
	Total assets acquired	238.6			(0.7		)	237.9
	Fair value of liabilities assumed:
	Accounts payable	20.8			—			20.8
	Current deferred tax liabilities	0.6			(0.6		)	—
	Accrued compensation and benefits	1.6			—			1.6
	Other accrued liabilities	12.3			(0.1		)	12.2
	Long term deferred tax liability	16.4			(0.2		)	16.2
	Other long term liabilities	0.4			—			0.4
	Total liabilities assumed	52.1			(0.9		)	51.2
	Redeemable noncontrolling interests	25.7			—			25.7
	Noncontrolling interests	5.8			—			5.8
	Net assets acquired	$	155		$	0.2		$	155.2
Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination	Other intangible assets acquired as a result of the acquisition of DWR were preliminarily valued at $69.3 million. These amounts are reflected in the values presented in the following table:
	Intangible Assets Acquired from the DWR Acquisition
	(In millions)	Fair Value			Useful Life
	Trade Names and Trademarks	$	55.1		Indefinite
	Exclusive Distribution Agreements	0.2			1.5 years
	Customer Relationships	12.8			10 - 16 years
	Product Development Designs	1.2			7 years
	Total Intangible Assets Acquired	$	69.3
Business Combinations Results of Operations of Acquiree	The following table provides net sales and results of operations from DWR included in the company’s results since the July 28, 2014 acquisition.
	DWR Results of Operations
		Three Months Ended			Nine Months Ended
	(In millions)	28-Feb-15			28-Feb-15
	DWR Net sales	$	59.5		$	147.9
	Intercompany sales elimination	(7.0		)	(14.4		)
	Net sales impact to Herman Miller, Inc.	$	52.5		$	133.5
	Net loss	$	(0.5	)	$	(4.3	)

Inventories_Tables

Inventories (Tables)	9 Months Ended
	Feb. 28, 2015
Inventories [Abstract]
Schedule of Inventory, Current
	(In millions)	28-Feb-15		31-May-14
	Finished goods	$	104.8	$	58.2
	Raw materials	23.7		20.2
	Total	$	128.5	$	78.4

Goodwill_and_Indefinitelived_I1

Goodwill and Indefinite-lived Intangibles (Tables)	9 Months Ended
	Feb. 28, 2015
Goodwill and Indefinite-lived Intangibles [Abstract]
Goodwill and Indefinite-lived Intangibles	Goodwill and other indefinite-lived intangible assets included in the Condensed Consolidated Balance Sheets consisted of the following as of February 28, 2015 and May 31, 2014:
	(In millions)	Goodwill			Indefinite-lived Intangible Assets		Total Goodwill and Indefinite-lived Intangible Assets
	May 31, 2014	$	228.2		$	40.9	$	269.1
	Foreign currency translation adjustments	(0.7		)	—		(0.7		)
	DWR acquisition	76.2			55.1		131.3
	February 28, 2015	$	303.7		$	96	$	399.7

Employee_Benefit_Plans_Tables

Employee Benefit Plans (Tables)	9 Months Ended
	Feb. 28, 2015
Employee Benefit Plans [Abstract]
Schedule of Defined Benefit Plans Disclosures	Components of Net Periodic Benefit Costs
	(In millions)	Three Months Ended
		Pension Benefits						Other Post-Retirement Benefits
		February 28, 2015			March 1, 2014			February 28, 2015		March 1, 2014
	Domestic:
	Interest cost	$	—		$	—		$	0.1	$	0.1
	Expected return on plan assets	—			—			—		—
	Net amortization loss	—			—			—		—
	Settlement loss recognized	—			—			—		—
	Net periodic benefit cost	$	—		$	—		$	0.1	$	0.1
	International:
	Interest cost	$	1.2		$	1
	Expected return on plan assets	(1.5		)	(1.2		)
	Net amortization loss	0.5			0.4
	Net periodic benefit cost	$	0.2		$	0.2
		Nine Months Ended
		Pension Benefits						Other Post-Retirement Benefits
		February 28, 2015			March 1, 2014			February 28, 2015		March 1, 2014
	Domestic:
	Interest cost	$	—		$	5.2		$	0.2	$	0.2
	Expected return on plan assets	—			(3.8		)	—		—
	Net amortization loss	—			4.8			—		—
	Settlement loss recognized	—			158.2			—		—
	Net periodic benefit cost	$	—		$	164.4		$	0.2	$	0.2
	International:
	Interest cost	$	3.5		$	3
	Expected return on plan assets	(4.5		)	(3.6		)
	Net amortization loss	1.5			1.2
	Net periodic benefit cost	$	0.5		$	0.6

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	9 Months Ended
	Feb. 28, 2015
Earnings Per Share [Abstract]
Schedule of Calculation of Numerator and Denominator in Earnings Per Share	The following table reconciles the numerators and denominators used in the calculations of basic and diluted earnings per share (EPS).
		Three Months Ended				Nine Months Ended
		February 28, 2015		March 1, 2014		February 28, 2015		March 1, 2014
	Numerators:
	Numerator for both basic and diluted EPS, net earnings - in millions	$	21	$	19.4	$	74.1	$	(38.7	)
	Denominators:
	Denominator for basic EPS, weighted-average common shares outstanding	59,550,289		59,014,789		59,430,575		58,888,514
	Potentially dilutive shares resulting from stock plans	547,900		638,628		566,292		—
	Denominator for diluted EPS	60,098,189		59,653,417		59,996,867		58,888,514
	Antidilutive equity awards not included in weighted-average common shares - diluted	676,405		780,800		703,364		2,782,663

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	9 Months Ended
	Feb. 28, 2015
Fair Value Disclosures [Abstract]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis	The following tables set forth financial assets and liabilities measured at fair value in the Condensed Consolidated Balance Sheets and the respective pricing levels to which the fair value measurements are classified within the fair value hierarchy as of February 28, 2015 and May 31, 2014.
	(In millions)	Fair Value Measurements
		February 28, 2015		May 31, 2014
	Financial Assets	Quoted Prices with		Quoted Prices with
		Other Observable Inputs		Other Observable Inputs
		(Level 2)		(Level 2)
	Available-for-sale marketable securities:
	Asset-backed securities	$	0.3	$	0.4
	Corporate securities	0.7		1.2
	Government obligations	4.9		7.9
	Mortgage-backed securities	0.5		1.6
	Foreign currency forward contracts	0.6		0.2
	Deferred compensation plan	7.6		6.3
	Total	$	14.6	$	17.6
	Financial Liabilities
	Foreign currency forward contracts	$	0.5	$	0.1
	Total	$	0.5	$	0.1
Unrealized Gain (Loss) on Investments	The following is a summary of the carrying and market values of the company's marketable securities as of the respective dates.
		February 28, 2015
	(In millions)	Cost		Unrealized		Unrealized		Market
				Gain		Loss		Value
	Asset-backed securities	$	0.3	$	—	$	—	$	0.3
	Corporate securities	0.7		—		—		0.7
	Government obligations	4.9		—		—		4.9
	Mortgage-backed securities	0.5		—		—		0.5
	Total	$	6.4	$	—	$	—	$	6.4
		May 31, 2014
	(In millions)	Cost		Unrealized		Unrealized		Market
				Gain		Loss		Value
	Asset-backed securities	$	0.4	$	—	$	—	$	0.4
	Corporate securities	1.2		—		—		1.2
	Government obligations	7.9		—		—		7.9
	Mortgage-backed securities	1.6		—		—		1.6
	Total	$	11.1	$	—	$	—	$	11.1
Investments Classified by Contractual Maturity Date	Maturities of debt securities included in marketable securities as of February 28, 2015, are as follows.
	(In millions)	Cost		Fair Value
	Due within one year	$	2.7	$	2.7
	Due after one year through five years	3.6		3.6
	Due after five years through ten years	—		—
	Due after more than ten years	0.1		0.1
	Total	$	6.4	$	6.4

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	9 Months Ended
	Feb. 28, 2015
Commitments and Contingencies Disclosure [Abstract]
Schedule of Product Warranty Liability	General warranty reserves are based on historical claims experience and other currently available information. These reserves are adjusted once an issue is identified and the actual cost of correction becomes known or can be estimated.
	(In millions)	Three Months Ended						Nine Months Ended
		February 28, 2015			March 1, 2014			February 28, 2015			March 1, 2014
	Accrual Balance — beginning	$	26		$	24.8		$	25.2		$	24.8
	Accrual for warranty matters	5.4			5.1			18.1			15.4
	Settlements and adjustments	(5.3		)	(4.5		)	(17.2		)	(14.8		)
	Accrual Balance — ending	$	26.1		$	25.4		$	26.1		$	25.4

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Income (Loss) (Tables)	9 Months Ended
	Feb. 28, 2015
Accumulated Other Comprehensive Income (Loss) [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss)	The following table provides an analysis of the changes in accumulated other comprehensive income (loss) for the nine months ended February 28, 2015 and March 1, 2014:
		Nine Months Ended
	(In millions)	February 28, 2015			March 1, 2014
	Cumulative translation adjustments at beginning of period	$	(11.1	)	$	(14.0	)
	Translation adjustments	(9.5		)	2.2
	Balance at end of period	(20.6		)	(11.8		)
	Pension and other post-retirement benefit plans at beginning of period	(26.8		)	(110.3		)
	Adjustments to pension and other post-retirement benefit plans	—			(2.0		)
	Reclassification to earnings - cost of sales (net of tax $0.0, $(15.9))	—			27.6
	Reclassification to earnings - operating expenses (net of tax $(0.3), $(35.7))	1.2			62.3
	Balance at end of period	(25.6		)	(22.4		)
	Total accumulated other comprehensive loss	$	(46.2	)	$	(34.2	)

Operating_Segments_Tables

Operating Segments (Tables)	9 Months Ended
	Feb. 28, 2015
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
Schedule of Segment Reporting Information, by Segment	The following is a summary of certain key financial measures for the respective fiscal periods indicated.
		Three Months Ended						Nine Months Ended
	(In millions)	February 28, 2015			March 1, 2014			February 28, 2015			March 1, 2014
	Net Sales:
	North American Furniture Solutions	$	296		$	293.9		$	932.4		$	909.2
	ELA Furniture Solutions	97.3			97.9			307			282.6
	Specialty	50.5			47.5			160.5			152.7
	Consumer	72.6			16.6			191.6			50
	Corporate	—			—			—			—
	Total	$	516.4		$	455.9		$	1,591.50		$	1,394.50
	Depreciation and Amortization:
	North American Furniture Solutions	$	7.2		$	7		$	21.4		$	20.8
	ELA Furniture Solutions	1.9			1.8			6.3			5.7
	Specialty	1.9			1.6			5.4			4.9
	Consumer	2.3			0.3			5.3			0.9
	Corporate	0.1			—			0.2			—
	Total	$	13.4		$	10.7		$	38.6		$	32.3
	Operating Earnings (Loss):
	North American Furniture Solutions	$	26.7		$	26.7		$	95.2		$	(58.3	)
	ELA Furniture Solutions	6.2			4.7			19.7			12.9
	Specialty	1.9			(0.2		)	7.6			(7.3		)
	Consumer	4.6			3.8			8.4			5.9
	Corporate	(2.0		)	(0.9		)	(4.6		)	(5.1		)
	Total	$	37.4		$	34.1		$	126.3		$	(51.9	)
	Capital Expenditures:
	North American Furniture Solutions	$	8		$	7.1		$	23.7		$	22.3
	ELA Furniture Solutions	7.3			3			13.6			5.6
	Specialty	0.6			1.9			2.8			4.1
	Consumer	0.6			—			3.1			—
	Corporate	—			—			—			—
	Total	$	16.5		$	12		$	43.2		$	32
	(In millions)	February 28, 2015			May 31, 2014
	Total Assets:
	North American Furniture Solutions	$	512.9		$	457
	ELA Furniture Solutions	236.2			244.8
	Specialty	154.1			157.7
	Consumer	221.4			18.8
	Corporate	68.2			112.6
	Total	$	1,192.80		$	990.9
	Total Goodwill:
	North American Furniture Solutions	$	135.8		$	135.8
	ELA Furniture Solutions	41.9			42.6
	Specialty	49.8			49.8
	Consumer	76.2			—
	Corporate	—			—
	Total	$	303.7		$	228.2

Fiscal_Year_Details

Fiscal Year (Details)	3 Months Ended		9 Months Ended
	Feb. 28, 2015	Mar. 01, 2014	Feb. 28, 2015	Mar. 01, 2014
Fiscal Year [Abstract]
Fiscal Period Duration, Quarter	91 days	91 days
Fiscal Period Duration, Year			364 days	364 days

Acquisitions_and_Divestitures_1

Acquisitions and Divestitures (Details) (USD $)	1 Months Ended	7 Months Ended	9 Months Ended	0 Months Ended	5 Months Ended	0 Months Ended	3 Months Ended
In Millions, unless otherwise specified	Aug. 30, 2014	Feb. 28, 2015	Feb. 28, 2015	Sep. 30, 2013	Mar. 01, 2014	Jul. 28, 2014	Nov. 30, 2013	Aug. 31, 2013	Mar. 01, 2014	31-May-14
							dealerships	dealerships	dealerships
Business Acquisition
Long-term Line of Credit						$127
Goodwill		303.7	303.7							228.2
Design Within Reach
Business Acquisition
Business Acquisition, Percentage of Voting Interests Acquired						81.00%
Purchase price		155.2
Business Acquisition, Goodwill, Expected Tax Deductible Amount						10
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests, Percent	4.00%
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	5.8
Business Combination, Acquisition Related Costs			2.2
Goodwill		76.2	76.2
Other intangible assets		69.3	69.3
Dongguan Sun Hing Steel Furniture Factory Ltd
Business Acquisition
Consideration transferred				8.2	6.7
Redeemable Noncontrolling Interest | Design Within Reach
Business Acquisition
Fair value of fully-vested options granted						$1.70
Herman Miller Consumer Holdings, Inc. | Design Within Reach
Business Acquisition
Capital Contributed, Percentage of Acquiree	15.00%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners						7.00%
ARKANSAS | Wholly-owned Contract Furniture Dealership
Business Acquisition
Numbers of Business Divested							1
OREGON | Wholly-owned Contract Furniture Dealership
Business Acquisition
Numbers of Business Divested								1
MONTREAL | Wholly-owned Contract Furniture Dealership
Business Acquisition
Numbers of Business Divested									1

Acquisitions_and_Divestitures_2

Acquisitions and Divestitures - Schedule of Business Acquisitions, by Acquisition (Details) (USD $)	7 Months Ended	1 Months Ended	6 Months Ended
In Millions, unless otherwise specified	Feb. 28, 2015	Aug. 30, 2014	Feb. 28, 2015	31-May-14
Fair value of the assets acquired:
Goodwill	$303.70		$303.70	$228.20
Design Within Reach
Business Acquisition
Purchase price	155.2
Fair value of the assets acquired:
Cash	1.2		1.2
Accounts receivable	2.2		2.2
Inventory	47.4		47.4
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets, Current	1.7		1.7
Other current assets	5.5		5.5
Long term deferred tax asset	0		0
Goodwill	76.2		76.2
Other intangible assets	69.3		69.3
Property	32		32
Other long term assets	2.4		2.4
Total assets acquired	237.9		237.9
Fair value of liabilities assumed:
Accounts payable	20.8		20.8
Current deferred tax liabilities	0		0
Accrued compensation and benefits	1.6		1.6
Other accrued liabilities	12.2		12.2
Long term deferred tax liability	16.2		16.2
Other long term liabilities	0.4		0.4
Total liabilities assumed	51.2		51.2
Redeemable noncontrolling interests	25.7		25.7
Noncontrolling interests	5.8		5.8
Net assets acquired	155.2		155.2
Scenario, Previously Reported [Member] | Design Within Reach
Business Acquisition
Purchase price		155
Fair value of the assets acquired:
Cash		1.2
Accounts receivable		2.4
Inventory		47.4
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets, Current		0
Other current assets		5.5
Long term deferred tax asset		3.7
Goodwill		74.4
Other intangible assets		69.6
Property		32
Other long term assets		2.4
Total assets acquired		238.6
Fair value of liabilities assumed:
Accounts payable		20.8
Current deferred tax liabilities		0.6
Accrued compensation and benefits		1.6
Other accrued liabilities		12.3
Long term deferred tax liability		16.4
Other long term liabilities		0.4
Total liabilities assumed		52.1
Redeemable noncontrolling interests		25.7
Noncontrolling interests		5.8
Net assets acquired		155
Scenario, Adjustment [Member] | Design Within Reach
Business Acquisition
Purchase price			0.2
Fair value of the assets acquired:
Cash	0		0
Accounts receivable	-0.2		-0.2
Inventory	0		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets, Current	1.7		1.7
Other current assets	0		0
Long term deferred tax asset	-3.7		-3.7
Goodwill	1.8		1.8
Other intangible assets	-0.3		-0.3
Property	0		0
Other long term assets	0		0
Total assets acquired	-0.7		-0.7
Fair value of liabilities assumed:
Accounts payable	0		0
Current deferred tax liabilities	-0.6		-0.6
Accrued compensation and benefits	0		0
Other accrued liabilities	-0.1		-0.1
Long term deferred tax liability	-0.2		-0.2
Other long term liabilities	0		0
Total liabilities assumed	-0.9		-0.9
Redeemable noncontrolling interests	0		0
Noncontrolling interests	0		0
Net assets acquired	$0.20		$0.20

Acquisitions_and_Divestitures_3

Acquisitions and Divestitures - Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination (Details) (USD $)	9 Months Ended	7 Months Ended
In Millions, unless otherwise specified	Feb. 28, 2015	Feb. 28, 2015
Business Acquisition
Trade Names and Trademarks	$55.10
Design Within Reach
Business Acquisition
Total Intangible Assets Acquired	69.3	69.3
Exclusive Distribution Agreements | Design Within Reach
Business Acquisition
Finite-lived Intangible Assets Acquired		0.2
Finite-Lived Intangible Asset, Useful Life		1 year 6 months
Customer Relationships | Design Within Reach
Business Acquisition
Finite-lived Intangible Assets Acquired		12.8
Product Development Designs | Design Within Reach
Business Acquisition
Finite-lived Intangible Assets Acquired		1.2
Finite-Lived Intangible Asset, Useful Life		7 years
Trade Names | Design Within Reach
Business Acquisition
Trade Names and Trademarks		$55.10

Aquisitions_and_Divestitures_A

Aquisitions and Divestitures Acquisitions and Divestitures - Business Combinations Results of of Operations of Acquiree (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Feb. 28, 2015	Mar. 01, 2014	Feb. 28, 2015	Mar. 01, 2014
Business Acquisition
Net sales	$516.40	$455.90	$1,591.50	$1,394.50
Design Within Reach
Business Acquisition
Net sales	59.5		147.9
Net sales impact to Herman Miller, Inc.	52.5		133.5
Net loss	-0.5		-4.3
Intercompany Segment Eliminations | Design Within Reach
Business Acquisition
Net sales	($7)		($14.40)

Acquisitions_and_Divestitures_4

Acquisitions and Divestitures - Phantom (Details) (Customer Relationships, Design Within Reach)	7 Months Ended
	Feb. 28, 2015
Minimum
Business Acquisition
Finite-Lived Intangible Asset, Useful Life	10 years
Maximum
Business Acquisition
Finite-Lived Intangible Asset, Useful Life	16 years

Inventories_Schedule_of_Invent

Inventories - Schedule of Inventory, Current (Details) (USD $)	Feb. 28, 2015	31-May-14
In Millions, unless otherwise specified
Inventories [Abstract]
Finished goods	$104.80	$58.20
Raw materials	23.7	20.2
Total	$128.50	$78.40

Goodwill_and_Indefinitelived_I2

Goodwill and Indefinite-lived Intangibles (Details) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Feb. 28, 2015
Goodwill [Roll Forward]
Goodwill, beginning	$228.20
Foreign currency translation adjustments	-0.7
DWR acquisition	76.2
Goodwill, ending	303.7
Indefinite-lived Intangible Assets [Roll Forward]
Indefinite-Lived Intangible Assets (Excluding Goodwill), beginning	40.9
Foreign currency translation adjustments	0
Trade Names and Trademarks	55.1
Indefinite-Lived Intangible Assets (Excluding Goodwill), ending	96
Rollforward of Goodwill and Indefinite-lived Intangible Assets [Roll Forward]
Goodwill and indefinite-lived intangibles, beginning	269.1
Foreign currency translation adjustments	-0.7
DWR acquisition	131.3
Goodwill and indefinite-lived intangibles, ending	$399.70

Employee_Benefit_Plans_Details

Employee Benefit Plans (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Feb. 28, 2015	Mar. 01, 2014	Feb. 28, 2015	Mar. 01, 2014
United States Pension Plan of US Entity
Defined Benefit Plan Disclosure
Interest cost	$0	$0	$0	$5.20
Expected return on plan assets	0	0	0	-3.8
Net amortization loss	0	0	0	4.8
Net periodic benefit cost	0	0	0	164.4
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements	0	0	0	158.2
Foreign Pension Plan
Defined Benefit Plan Disclosure
Interest cost	1.2	1	3.5	3
Expected return on plan assets	-1.5	-1.2	-4.5	-3.6
Net amortization loss	0.5	0.4	1.5	1.2
Net periodic benefit cost	0.2	0.2	0.5	0.6
United States Postretirement Benefit Plan of US Entity
Defined Benefit Plan Disclosure
Interest cost	0.1	0.1	0.2	0.2
Expected return on plan assets	0	0	0	0
Net amortization loss	0	0	0	0
Net periodic benefit cost	0.1	0.1	0.2	0.2
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements	$0	$0	$0	$0

Earnings_Per_Share_Details

Earnings Per Share (Details)	3 Months Ended		9 Months Ended
	Feb. 28, 2015	Mar. 01, 2014	Feb. 28, 2015	Mar. 01, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive equity awards not included in weighted-average common shares	676,405	780,800	703,364	2,782,663
Equity Option
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive equity awards not included in weighted-average common shares	676,405	765,448	703,364	2,134,500

Earnings_Per_Share_Earnings_Pe

Earnings Per Share Earnings Per Share - Schedule of Calculation of Numerator and Denominator in Earnings Per Share (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, except Share data, unless otherwise specified	Feb. 28, 2015	Mar. 01, 2014	Feb. 28, 2015	Mar. 01, 2014
Earnings Per Share [Abstract]
Numerator for both basic and diluted EPS, net earnings - in millions	$21	$19.40	$74.10	($38.70)
Denominator for basic EPS, weighted-average common shares outstanding	59,550,289	59,014,789	59,430,575	58,888,514
Potentially dilutive shares resulting from stock plans	547,900	638,628	566,292	0
Denominator for diluted EPS	60,098,189	59,653,417	59,996,867	58,888,514
Antidilutive equity awards not included in weighted-average common shares - diluted	676,405	780,800	703,364	2,782,663

StockBased_Compensation_Detail

Stock-Based Compensation (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, except Share data, unless otherwise specified	Feb. 28, 2015	Mar. 01, 2014	Feb. 28, 2015	Mar. 01, 2014
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Allocated Share-based Compensation Expense	$2.40	$2.70	$8.10	$8.30
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	$0.80	$1	$2.90	$3
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period			258,927	412,541
Common Stock, Capital Shares Reserved for Future Issuance	4,000,000		4,000,000
Percent of Market Price	85.00%		85.00%
Restricted Stock Units (RSUs)
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised			130,144	108,947
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Conversion Ratio to Common Stock			1
Employee Stock Option
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period			10 years
Restricted Stock [Member]
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			5 years
Phantom Share Units (PSUs) [Member]
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			3 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Conversion Ratio to Common Stock			1
Minimum | Restricted Stock Units (RSUs)
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			3 years
Minimum | Employee Stock Option
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			1 year
Maximum | Restricted Stock Units (RSUs)
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			5 years
Maximum | Employee Stock Option
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			3 years
Herman Miller Consumer Holdings | Minimum | Employee Stock Option
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			1 year
Herman Miller Consumer Holdings | Maximum | Employee Stock Option
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			5 years

StockBased_Compensation_StockB

Stock-Based Compensation Stock-Based Compensation - Phantom (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Feb. 28, 2015	Mar. 01, 2014	Feb. 28, 2015	Mar. 01, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	$0.80	$1	$2.90	$3

Income_Taxes_Details

Income Taxes (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Feb. 28, 2015	Mar. 01, 2014	Feb. 28, 2015	Mar. 01, 2014
Income Tax Disclosure [Abstract]
Effective Income Tax Rate, Continuing Operations	33.60%	33.30%	33.50%	41.10%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			35.00%
Liability for Uncertain Tax Positions, Current	$1.50	$1.70	$1.50	$1.70
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	0.2	0	0.3	0
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	$0.90	$0.70	$0.90	$0.70

Income_Taxes_Phantom_Details

Income Taxes - Phantom (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Feb. 28, 2015	Mar. 01, 2014	Feb. 28, 2015	Mar. 01, 2014
Income Tax Disclosure [Abstract]
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	$0.20	$0	$0.30	$0

Fair_Value_Measurements_Fair_V

Fair Value Measurements - Fair Value Hierarchy (Details) (Fair Value, Inputs, Level 2, Fair Value, Measurements, Recurring, USD $)	Feb. 28, 2015	31-May-14
In Millions, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Deferred Compensation Plan Fair Value Disclosure	$7.60	$6.30
Assets, Fair Value Disclosure	14.6	17.6
Financial and Nonfinancial Liabilities, Fair Value Disclosure	0.5	0.1
Foreign Exchange Forward
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Foreign Currency Contract, Asset, Fair Value Disclosure	0.6	0.2
Foreign Currency Contracts, Liability, Fair Value Disclosure	0.5	0.1
Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale marketable securities	0.3	0.4
Corporate Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale marketable securities	0.7	1.2
US Treasury and Government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale marketable securities	4.9	7.9
Collateralized Mortgage Backed Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale marketable securities	$0.50	$1.60

Fair_Value_Measurements_Unreal

Fair Value Measurements - Unrealized Gain (Loss) on Investments (Details) (USD $)	Feb. 28, 2015	31-May-14
In Millions, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cost	$6.40	$11.10
Unrealized Gain	0	0
Unrealized Loss	0	0
Market Value	6.4	11.1
Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cost	0.3	0.4
Unrealized Gain	0	0
Unrealized Loss	0	0
Market Value	0.3	0.4
Corporate Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cost	0.7	1.2
Unrealized Gain	0	0
Unrealized Loss	0	0
Market Value	0.7	1.2
US Treasury and Government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cost	4.9	7.9
Unrealized Gain	0	0
Unrealized Loss	0	0
Market Value	4.9	7.9
Collateralized Mortgage Backed Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cost	0.5	1.6
Unrealized Gain	0	0
Unrealized Loss	0	0
Market Value	$0.50	$1.60

Fair_Value_Measurements_Maturi

Fair Value Measurements - Maturities of Available-for-sale marketable securities (Details) (USD $)	Feb. 28, 2015	31-May-14
In Millions, unless otherwise specified
Fair Value Disclosures [Abstract]
Available-for-sale Securities, Debt Maturities, within One Year, Amortized Cost Basis	$2.70
Available-for-sale Securities, Debt Maturities, within One Year, Fair Value	2.7
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Amortized Cost Basis	3.6
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Fair Value	3.6
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Amortized Cost Basis	0
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Fair Value	0
Available-for-sale Securities, Debt Maturities, after Ten Years, Amortized Cost Basis	0.1
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	0.1
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis	$6.40	$11.10

Commitments_and_Contingencies_1

Commitments and Contingencies (Details) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Feb. 28, 2015	31-May-14
Schedule of Warranty Accrual
Warranty Length	12 years
Performance Guarantee
Schedule of Warranty Accrual
Guarantor Obligations, Maximum Exposure, Undiscounted	9.1
Guarantor Obligations, Current Carrying Value	0	0
Financial Standby Letter of Credit
Schedule of Warranty Accrual
Guarantor Obligations, Maximum Exposure, Undiscounted	8.3
Guarantor Obligations, Current Carrying Value	0	0
Minimum | Performance Guarantee
Schedule of Warranty Accrual
Guarantor Obligations, Period	1 year
Maximum | Performance Guarantee
Schedule of Warranty Accrual
Guarantor Obligations, Period	3 years
Necessary Maintenance And Repairs
Schedule of Warranty Accrual
Loss Contingency, Range of Possible Loss, Minimum	0
Loss Contingency, Range of Possible Loss, Maximum	3
Other Accrued Liabilities | Necessary Maintenance And Repairs
Schedule of Warranty Accrual
Loss Contingency Accrual	1.2	$1.50

Commitments_and_Contingencies_2

Commitments and Contingencies - Schedule of Product Warranty Liability (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Feb. 28, 2015	Mar. 01, 2014	Feb. 28, 2015	Mar. 01, 2014
Movement in Standard Product Warranty Accrual [Roll Forward]
Accrual Balance — beginning	$26	$24.80	$25.20	$24.80
Accrual for warranty matters	5.4	5.1	18.1	15.4
Settlements and adjustments	-5.3	-4.5	-17.2	-14.8
Accrual Balance — ending	$26.10	$25.40	$26.10	$25.40

Commitments_and_Contingencies_3

Commitments and Contingencies - Phantom (Details) (USD $)	Feb. 28, 2015	31-May-14
In Millions, unless otherwise specified
Performance Guarantee
Loss Contingencies [Line Items]
Guarantor Obligations, Current Carrying Value	$0	$0
Financial Standby Letter of Credit
Loss Contingencies [Line Items]
Guarantor Obligations, Current Carrying Value	$0	$0

Debt_Details

Debt (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Feb. 28, 2015	Jul. 28, 2014	31-May-14
Line of Credit Facility
Current maturities of long-term debt	$0		$50
Long-term Line of Credit		127
Borrowings on revolver and outstanding letters of credit	134.3
Letters of Credit Outstanding, Amount			4.9
Extinguishment of Debt, Type [Domain]
Line of Credit Facility
Repayments of Debt	50
Revolving Line of Credit, Domestic
Line of Credit Facility
Line of Credit Facility, Maximum Borrowing Capacity	250		150
Line Of Credit Facility, Increase in Borrowing Capacity	125		75
Long-term Line of Credit	126
Letters of Credit Outstanding, Amount	8.3
South China Ops [Member] | Revolving Line of Credit, Foreign
Line of Credit Facility
Long-term Line of Credit	0		0
Ningbo [Member] | Revolving Line of Credit, Foreign
Line of Credit Facility
Long-term Line of Credit	0		0
Line of Credit Facility, Current Borrowing Capacity	$5

Debt_Debt_Phantom_Details

Debt Debt - Phantom (Details) (USD $)	Jul. 28, 2014	Feb. 28, 2015	31-May-14
In Millions, unless otherwise specified
Line of Credit Facility
Long-term Line of Credit	$127
South China Ops | Revolving Line of Credit, Foreign
Line of Credit Facility
Long-term Line of Credit		0	0
Ningbo | Revolving Line of Credit, Foreign
Line of Credit Facility
Long-term Line of Credit		$0	$0

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive Income (Loss) (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Feb. 28, 2015	Mar. 01, 2014	Feb. 28, 2015	Mar. 01, 2014	31-May-14
Cumulative translation adjustments [Roll Forward]
Cumulative translation adjustments at beginning of period			($11.10)	($14)
Translation adjustments	-3.6	0.1	-9.5	2.2
Balance at end of period	-20.6	-11.8	-20.6	-11.8
Pension and other post-retirement benefit plans [Roll Forward]
Pension and other post-retirement benefit plans at beginning of period			-26.8	-110.3
Adjustments to pension and other post-retirement benefit plans			0	-2
Balance at end of period	-25.6	-22.4	-25.6	-22.4
Total accumulated other comprehensive loss	-46.2	-34.2	-46.2	-34.2	-37.9
Cost of Sales
Pension and other post-retirement benefit plans [Roll Forward]
Reclassification Adjustment from AOCI, Pension and Other Postretirement Plans, Net of Tax			0	27.6
Reclassification Adjustment from AOCI, Pension and Other Postretirement Plans, Tax			0	-15.9
Operating Expense
Pension and other post-retirement benefit plans [Roll Forward]
Reclassification Adjustment from AOCI, Pension and Other Postretirement Plans, Net of Tax			1.2	62.3
Reclassification Adjustment from AOCI, Pension and Other Postretirement Plans, Tax			($0.30)	($35.70)

Restructuring_and_Impairment_A1

Restructuring and Impairment Activities (Details) (USD $)	3 Months Ended			9 Months Ended
In Millions, unless otherwise specified	Feb. 28, 2015	Mar. 01, 2014	Nov. 30, 2013	Feb. 28, 2015	Mar. 01, 2014
Restructuring and Related Activities
Restructuring and Impairment Expenses	$1.90	$1.10		$1.90	$5.10
Tangible Asset Impairment Charges			$4

Operating_Segments_Details

Operating Segments (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Feb. 28, 2015	Mar. 01, 2014	Feb. 28, 2015	Mar. 01, 2014	31-May-14
Segment Reporting Information
Net Sales:	$516.40	$455.90	$1,591.50	$1,394.50
Depreciation and Amortization:	13.4	10.7	38.6	32.3
Operating Earnings (Loss):	37.4	34.1	126.3	-51.9
Capital Expenditures:	16.5	12	43.2	32
Total Assets:	1,192.80		1,192.80		990.9
Total Goodwill:	303.7		303.7		228.2
North American Furniture Solutions
Segment Reporting Information
Net Sales:	296	293.9	932.4	909.2
Depreciation and Amortization:	7.2	7	21.4	20.8
Operating Earnings (Loss):	26.7	26.7	95.2	-58.3
Capital Expenditures:	8	7.1	23.7	22.3
Total Assets:	512.9		512.9		457
Total Goodwill:	135.8		135.8		135.8
ELA Furniture Solutions
Segment Reporting Information
Net Sales:	97.3	97.9	307	282.6
Depreciation and Amortization:	1.9	1.8	6.3	5.7
Operating Earnings (Loss):	6.2	4.7	19.7	12.9
Capital Expenditures:	7.3	3	13.6	5.6
Total Assets:	236.2		236.2		244.8
Total Goodwill:	41.9		41.9		42.6
Specialty
Segment Reporting Information
Net Sales:	50.5	47.5	160.5	152.7
Depreciation and Amortization:	1.9	1.6	5.4	4.9
Operating Earnings (Loss):	1.9	-0.2	7.6	-7.3
Capital Expenditures:	0.6	1.9	2.8	4.1
Total Assets:	154.1		154.1		157.7
Total Goodwill:	49.8		49.8		49.8
Consumer
Segment Reporting Information
Net Sales:	72.6	16.6	191.6	50
Depreciation and Amortization:	2.3	0.3	5.3	0.9
Operating Earnings (Loss):	4.6	3.8	8.4	5.9
Capital Expenditures:	0.6	0	3.1	0
Total Assets:	221.4		221.4		18.8
Total Goodwill:	76.2		76.2		0
Corporate
Segment Reporting Information
Net Sales:	0	0	0	0
Depreciation and Amortization:	0.1	0	0.2	0
Operating Earnings (Loss):	-2	-0.9	-4.6	-5.1
Capital Expenditures:	0	0	0	0
Total Assets:	68.2		68.2		112.6
Total Goodwill:	$0		$0		$0

Subsequent_Event_Details

Subsequent Event (Details) (Assets Held-for-sale [Member], USD $)	Feb. 28, 2015
In Millions, unless otherwise specified
Assets Held-for-sale [Member]
Subsequent Event [Line Items]
Assets Held-for-sale, Long Lived, Fair Value Disclosure	$4.20