MillerKnoll (MLKN) 10-Q 7 Jan 15 2015 Q2 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	6 Months Ended
	Nov. 29, 2014	Jan. 05, 2015
Document Entity Information [Abstract]
Entity Registrant Name	MILLER HERMAN INC
Entity Central Index Key	66382
Document Type	10-Q
Document Period End Date	29-Nov-14
Amendment Flag	FALSE
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	-25
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		59,594,395

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $)	3 Months Ended		6 Months Ended
In Millions, except Per Share data, unless otherwise specified	Nov. 29, 2014	Nov. 30, 2013	Nov. 29, 2014	Nov. 30, 2013
Income Statement [Abstract]
Net sales	$565.40	$470.50	$1,075.10	$938.60
Cost of sales	359.7	351.6	683.8	649.7
Gross margin	205.7	118.9	391.3	288.9
Operating expenses:
Selling, general, and administrative	141.1	223.6	267.8	338
Restructuring and impairment expenses	0	4	0	4
Design and research	17.9	16.5	34.6	33
Total operating expenses	159	244.1	302.4	375
Operating earnings (loss)	46.7	-125.2	88.9	-86.1
Other expenses:
Interest expense	4.6	4.3	9.3	8.8
Other, net	0.1	-0.2	0.1	-0.1
Earnings before income taxes and equity income	42	-129.3	79.5	-94.8
Income tax expense (benefit)	14.2	-48.6	26.6	-36.6
Equity earnings from nonconsolidated affiliates, net of tax	0	0.1	0.1	0.1
Net earnings (loss)	27.8	-80.6	53	-58.1
Net earnings attributable to noncontrolling interests	0	0	0	0
Net earnings (loss) attributable to Herman Miller, Inc.	27.8	-80.6	53	-58.1
Earnings (loss) per share — basic	$0.47	($1.37)	$0.89	($0.99)
Earnings (loss) per share — diluted	$0.46	($1.37)	$0.88	($0.99)
Dividends declared, per share	$0.14	$0.13	$0.28	$0.25
Other comprehensive income, net of tax
Foreign currency translation adjustments	-5.4	2.8	-5.9	2.1
Pension and post-retirement liability adjustments	0.5	86.2	0.9	87.6
Other comprehensive income (loss)	-4.9	89	-5	89.7
Comprehensive income	22.9	8.4	48	31.6
Comprehensive income attributable to noncontrolling interests	0	0	0	0
Comprehensive income attributable to Herman Miller, Inc.	$22.90	$8.40	$48	$31.60

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (Unaudited) (USD $)	Nov. 29, 2014	31-May-14
In Millions, unless otherwise specified
Current Assets:
Cash and cash equivalents	$64.70	$101.50
Marketable securities	6.6	11.1
Accounts and notes receivable, net	198.6	204.3
Inventories, net	126.3	78.4
Prepaid expenses and other	65.1	56.5
Total current assets	461.3	451.8
Property and equipment, at cost	846.5	789.2
Less — accumulated depreciation	-612.4	-594
Net property and equipment	234.1	195.2
Goodwill	303.9	228.2
Indefinite-lived intangibles	96	40.9
Other amortizable intangibles, net	55.7	44.2
Other noncurrent assets	42.9	30.6
Total Assets	1,193.90	990.9
Current Liabilities:
Current maturities of long-term debt	50	50
Accounts payable	160.7	136.9
Accrued compensation and benefits	62.4	65
Accrued warranty	26	25.2
Other accrued liabilities	93.2	79
Total current liabilities	392.3	356.1
Long-term debt	277	200
Pension and post-retirement benefits	16.5	18.2
Other liabilities	69.8	44.5
Total Liabilities	755.6	618.8
Redeemable noncontrolling interests	27	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	130.4	122.4
Retained earnings	313.6	277.4
Accumulated other comprehensive loss	-42.9	-37.9
Key executive deferred compensation plans	-1.7	-1.7
Total Stockholder's Equity	411.3	372.1
Total Liabilities, Redeemable Noncontrolling Interest, and Stockholders' Equity	$1,193.90	$990.90

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Parentheticals) (USD $)	Nov. 29, 2014	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 $)	6 Months Ended
In Millions, unless otherwise specified	Nov. 29, 2014	Nov. 30, 2013
Statement of Cash Flows [Abstract]
Net earnings (loss)	$53	($58.10)
Adjustments to reconcile net earnings (loss) to net cash provided by operating activities:
Depreciation and amortization	25.2	21.6
Stock-based compensation	5.7	5.6
Excess tax benefits from stock-based compensation	-0.6	-0.8
Pension and post-retirement expenses	0.6	116.4
Deferred taxes	-5.4	-49
Gain on sales of property and dealers	-0.2	-0.3
Restructuring and impairment expenses	0	4
Other, net	0.4	0.3
Increase in current assets	-1.7	-11.9
Increase in current liabilities	3.3	6
(Increase) Decrease in non-current liabilities	0.4	-6.3
Net Cash Provided by Operating Activities	80.7	27.5
Cash Flows from Investing Activities:
Proceeds from sales of property and dealers	0.3	0
Marketable securities purchases	0	-3.2
Marketable securities sales	4.5	2.5
Acquisitions, net of cash received	-154	-5.9
Capital expenditures	-26.7	-20
Other, net	-0.6	0.3
Net Cash Used in Investing Activities	-176.5	-26.3
Cash Flows from Financing Activities:
Dividends paid	-16.6	-14.7
Proceeds from issuance of long-term debt	401.5	0
Payments of long-term debt	-324.5	0
Common stock issued	5.7	8.9
Common stock repurchased and retired	-3.2	-4.1
Excess tax benefits from stock-based compensation	0.6	0.8
Payment of contingent consideration obligation	0	-1.3
Purchase of noncontrolling interests	-5.8	0
Other, net	0.8	0.1
Net Cash Provided by/(Used in) Financing Activities	58.5	-10.3
Effect of Exchange Rate Changes on Cash and Cash Equivalents	0.5	-0.3
Net Increase (Decrease) in Cash and Cash Equivalents	-36.8	-9.4
Cash and Cash Equivalents, Beginning of Period	101.5	82.7
Cash and Cash Equivalents, End of Period	$64.70	$73.30

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
Redeemable Noncontrolling Interest, Equity, Increase from Sale of Interest in Subsidiary Equity	0
Redeemable Noncontrolling Interest, Equity, Increase from Exercise of Stock Option	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchase and retirement of common stock				-4.1
Exercise of stock options			0.1	8
Stock-based compensation expense				5.6
Excess tax benefit for stock-based compensation				0.7
Restricted stock units released				0.1
Employee stock purchase plan issuances				0.8
Net income attributable to Herman Miller, Inc.	-58.1				-58.1
Dividends declared, per share	$0.25
Dividends declared on common stock (per share - 2015: $0.280; 2014; $0.250)					-14.9
Other comprehensive income (loss)	89.7					89.7
Deferred compensation plan							0
Noncontrolling interests related to DWR acquisition								0
Purchase of noncontrolling interests								0
Balance at end of period at Nov. 30, 2013	347.4	0	11.8	114	258.1	-34.6	-1.9	0
Redeemable noncontrolling interests at Nov. 30, 2013	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	0.5
Redeemable Noncontrolling Interest, Equity, Increase from Sale of Interest in Subsidiary Equity	0.1
Redeemable Noncontrolling Interest, Equity, Increase from Exercise of Stock Option	0.7
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchase and retirement of common stock				-3.2
Exercise of stock options			0	4.9
Stock-based compensation expense				5.2
Excess tax benefit for stock-based compensation				0.2
Restricted stock units released				0.1
Employee stock purchase plan issuances				0.8
Net income attributable to Herman Miller, Inc.	53				53
Dividends declared, per share	$0.28
Dividends declared on common stock (per share - 2015: $0.280; 2014; $0.250)					-16.8
Other comprehensive income (loss)	-5					-5
Deferred compensation plan							0
Noncontrolling interests related to DWR acquisition								5.8
Purchase of noncontrolling interests								-5.8
Balance at end of period at Nov. 29, 2014	411.3	0	11.9	130.4	313.6	-42.9	-1.7	0
Redeemable noncontrolling interests at Nov. 29, 2014	$27

Basis_of_Presentation

Basis of Presentation	6 Months Ended
	Nov. 29, 2014
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 November 29, 2014. Operating results for the six months ended November 29, 2014, 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	6 Months Ended
	Nov. 29, 2014
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 November 29, 2014
	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, and early adoption is not permitted. The company is currently evaluating the impact of adopting this guidance.

Fiscal_Year

Fiscal Year	6 Months Ended
	Nov. 29, 2014
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 second quarter of fiscal 2015 and fiscal 2014 each contained 13 weeks.

Acquisitions_and_Divestitures

Acquisitions and Divestitures	6 Months Ended
	Nov. 29, 2014
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 November 29, 2014
	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
	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			1.3			239.9
	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			—			12.3
	Long term deferred tax liability	16.4			1.1			17.5
	Other long term liabilities	0.4			—			0.4
	Total liabilities assumed	52.1			1.1			53.2
	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 Design Within Reach 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			Six Months Ended
	(In millions)	July 28, 2014 - August 30, 2014			29-Nov-14			29-Nov-14
	DWR Net sales	$	21.6		$	66.8		$	88.4
	Intercompany sales elimination	(1.6		)	(5.8		)	(7.4		)
	Net sales impact to Herman Miller, Inc.	$	20		$	61		$	81
	Net loss	$	(1.6	)	$	(2.2	)	$	(3.8	)
	DWR Acquisition-related expenses were $0.2 million for the second quarter and were $2.2 million for the six-month period. 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 second quarter of fiscal 2014, the company completed the sale of one wholly-owned contract furniture dealership in Arkansas. 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 during the first quarter of fiscal 2014. The effect of this transaction on the company's consolidated financial statements was also not material.

Inventories

Inventories	6 Months Ended
	Nov. 29, 2014
Inventories [Abstract]
Inventory Disclosure	INVENTORIES, NET
	(In millions)	29-Nov-14		31-May-14
	Finished goods	$	102.7	$	58.2
	Raw materials	23.6		20.2
	Total	$	126.3	$	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	6 Months Ended
	Nov. 29, 2014
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 November 29, 2014 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	(0.5		)	—		(0.5		)
	DWR acquisition	76.2			55.1		131.3
	November 29, 2014	$	303.9		$	96	$	399.9

Employee_Benefit_Plans

Employee Benefit Plans	6 Months Ended
	Nov. 29, 2014
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 either a lump sum distribution, 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
		November 29, 2014			November 30, 2013			November 29, 2014		November 30, 2013
	Domestic:
	Interest cost	$	—		$	2.6		$	0.1	$	0.1
	Expected return on plan assets	—			(1.9		)	—		—
	Net amortization loss	—			2.4			—		—
	Settlement loss recognized	—			158.2			—		—
	Net periodic benefit cost	$	—		$	161.3		$	0.1	$	0.1
	International:
	Interest cost	$	1.1		$	1
	Expected return on plan assets	(1.5		)	(1.2		)
	Net amortization loss	0.5			0.4
	Net periodic benefit cost	$	0.1		$	0.2
		Six Months Ended
		Pension Benefits						Other Post-Retirement Benefits
		29-Nov-14			30-Nov-13			29-Nov-14		30-Nov-13
	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	$	2.3		$	2
	Expected return on plan assets	(3.0		)	(2.4		)
	Net amortization loss	1			0.8
	Net periodic benefit cost	$	0.3		$	0.4

Earnings_Per_Share

Earnings Per Share	6 Months Ended
	Nov. 29, 2014
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					Six Months Ended
		November 29, 2014		November 30, 2013			November 29, 2014		November 30, 2013
	Numerators:
	Numerator for both basic and diluted EPS, net earnings - in millions	$	27.8	$	(80.6	)	$	53	$	(58.1	)
	Denominators:
	Denominator for basic EPS, weighted-average common shares outstanding	59,445,577		58,923,648			59,370,718		58,825,377
	Potentially dilutive shares resulting from stock plans	578,941		—			581,916		—
	Denominator for diluted EPS	60,024,518		58,923,648			59,952,634		58,825,377
	Antidilutive equity awards not included in weighted-average common shares - diluted	538,380		2,780,570			743,060		2,867,150
	The total antidilutive equity awards not included in the weighted-average common shares for the second quarter of fiscal 2015 and fiscal 2014 were 538,380 shares and 2,780,570 shares, respectively. Included within these amounts were options to purchase 507,252 shares and 2,094,277 shares, respectively.
	For the six months ended November 29, 2014 and November 30, 2013, the total antidilutive equity shares not included in the weighted-average common shares were 743,060 shares and 2,867,150 shares, respectively. Included within these amounts were options to purchase 716,843 shares and 2,191,741 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	6 Months Ended
	Nov. 29, 2014
Stock-Based Compensation [Abstract]
Stock-Based Compensation	STOCK-BASED COMPENSATION
	The company's stock-based compensation expense for the three month periods ended November 29, 2014 and November 30, 2013 was $2.7 million and $2.8 million, respectively. The related income tax effect for the three month periods ended November 29, 2014 and November 30, 2013 was $1.0 million. For the six months ended November 29, 2014 and November 30, 2013, compensation costs were $5.7 million and $5.6 million, respectively. The related income tax effect for the respective six month periods was $2.1 million and $2.0 million, respectively.
	Stock-based compensation expense recognized in the Condensed Consolidated Statements of Comprehensive Income for the three and six month periods ended November 29, 2014 and November 30, 2013 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 six month period ended November 29, 2014, the company issued 226,867 shares of common stock related to the exercise of stock options and 121,985 of common stock related to the vesting of restricted stock units.
	For the six month period ended November 30, 2013, the company issued 390,080 shares of common stock related to the exercise of stock options and 93,041 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 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 lapses. 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 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	6 Months Ended
	Nov. 29, 2014
Income Tax Disclosure [Abstract]
Income Tax Disclosure	INCOME TAXES
	The effective tax rates for the three months ended November 29, 2014 and November 30, 2013, were 33.8 percent and 37.6 percent, respectively. The company's United States federal statutory rate is 35 percent. For the six month periods ended November 29, 2014 and November 30, 2013, the effective tax rates were 33.4 percent and 38.7 percent, respectively. The decrease in the rate in the quarter ended November 29, 2014 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 $1.4 million as of both November 29, 2014 and November 30, 2013.
	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 $0.1 million during the six month periods ended November 29, 2014 and November 30, 2013 and were negligible during the three month periods ended November 29, 2014 and November 30, 2013. The company's recorded liability for potential interest and penalties related to uncertain tax benefits totaled $0.7 million and $0.6 million as of November 29, 2014 and November 30, 2013, 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	6 Months Ended
	Nov. 29, 2014
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 November 29, 2014 and May 31, 2014.
	(In millions)	Fair Value Measurements
		November 29, 2014		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	0.8		1.2
	Government obligations	4.9		7.9
	Mortgage-backed securities	0.6		1.6
	Foreign currency forward contracts	0.4		0.2
	Deferred compensation plan	7.2		6.3
	Total	$	14.2	$	17.6
	Financial Liabilities
	Foreign currency forward contracts	$	0.3	$	0.1
	Total	$	0.3	$	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.
		November 29, 2014
	(In millions)	Cost		Unrealized		Unrealized		Market
				Gain		Loss		Value
	Asset-backed securities	$	0.3	$	—	$	—	$	0.3
	Corporate securities	0.8		—		—		0.8
	Government obligations	4.9		—		—		4.9
	Mortgage-backed securities	0.6		—		—		0.6
	Total	$	6.6	$	—	$	—	$	6.6
		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 November 29, 2014, are as follows.
	(In millions)	Cost		Fair Value
	Due within one year	$	1.1	$	1.1
	Due after one year through five years	5.5		5.5
	Due after five years through ten years	—		—
	Total	$	6.6	$	6.6
	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	6 Months Ended
	Nov. 29, 2014
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						Six Months Ended
		November 29, 2014			November 30, 2013			November 29, 2014			November 30, 2013
	Accrual Balance — beginning	$	25.7		$	24.6		$	25.2		$	24.8
	Accrual for warranty matters	6.2			5.4			12.7			10.3
	Settlements and adjustments	(5.9		)	(5.2		)	(11.9		)	(10.3		)
	Accrual Balance — ending	$	26		$	24.8		$	26		$	24.8
	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 November 29, 2014, the company had a maximum financial exposure related to performance bonds totaling approximately $10.4 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 as of November 29, 2014 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 November 29, 2014, the company had a maximum financial exposure from these standby letters of credit totaling approximately $10.6 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 as of November 29, 2014 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 November 29, 2014, 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	6 Months Ended
	Nov. 29, 2014
Debt Disclosure [Abstract]
Debt Disclosure	DEBT
	The company's Series A Senior Notes are due on January 3, 2015. Due to this upcoming maturity, $50 million is classified within the Condensed Consolidated Balance Sheet as "Current maturities of long-term debt".
	On July 21, 2014, the company entered into a third amendment and restatement of the 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 November 29, 2014, the total debt outstanding related to borrowings against this facility was $77.0 million. These borrowings are included within Long-term debt in the Condensed Consolidated Balance Sheet. The total usage against the facility was $87.6 million, of which $10.6 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 November 29, 2014 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 November 29, 2014 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)	6 Months Ended
	Nov. 29, 2014
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 six months ended November 29, 2014 and November 30, 2013:
		Six Months Ended
	(In millions)	November 29, 2014			November 30, 2013
	Cumulative translation adjustments at beginning of period	$	(11.1	)	$	(14.0	)
	Translation adjustments	(5.9		)	2.1
	Balance at end of period	(17.0		)	(11.9		)
	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 $(0.2), $(35.7))	0.9			62
	Balance at end of period	(25.9		)	(22.7		)
	Total accumulated other comprehensive loss	$	(42.9	)	$	(34.6	)

Restructuring_Activities_Notes

Restructuring Activities (Notes)	6 Months Ended
	Nov. 29, 2014
Restructuring and Related Activities [Abstract]
Restructuring and Related Activities Disclosure [Text Block]	RESTRUCTURING AND IMPAIRMENT ACTIVITIES
	Due to the acquisition of a manufacturing and distribution operation in Dongguan, China in the second quarter of 2014, Herman Miller
	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	6 Months Ended
	Nov. 29, 2014
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 Design Within Reach 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						Six Months Ended
	(In millions)	November 29, 2014			November 30, 2013			November 29, 2014			November 30, 2013
	Net Sales:
	North American Furniture Solutions	$	315.3		$	297.1		$	636.4		$	615.3
	ELA Furniture Solutions	114.3			103.1			209.7			184.7
	Specialty	55.4			53.2			110			105.2
	Consumer	80.4			17.1			119			33.4
	Corporate	—			—			—			—
	Total	$	565.4		$	470.5		$	1,075.10		$	938.6
	Depreciation and Amortization:
	North American Furniture Solutions	$	7		$	7.6		$	14.2		$	14.7
	ELA Furniture Solutions	2.2			1.4			4.4			3.4
	Specialty	1.8			1.3			3.5			3
	Consumer	2.1			0.2			3			0.5
	Corporate	0.1			—			0.1			—
	Total	$	13.2		$	10.5		$	25.2		$	21.6
	Operating Earnings:
	North American Furniture Solutions	$	32.3		$	(119.0	)	$	68.5		$	(85.0	)
	ELA Furniture Solutions	10.4			8.2			13.5			8.1
	Specialty	2.8			(8.9		)	5.7			(7.1		)
	Consumer	1.5			(1.3		)	3.8			2.1
	Corporate	(0.3		)	(4.2		)	(2.6		)	(4.2		)
	Total	$	46.7		$	(125.2	)	$	88.9		$	(86.1	)
	Capital Expenditures:
	North American Furniture Solutions	$	11.5		$	10.8		$	15.7		$	15.3
	ELA Furniture Solutions	4.4			1.2			6.3			2.6
	Specialty	1.1			1.5			2.2			2.1
	Consumer	1.5			—			2.5			—
	Corporate	—			—			—			—
	Total	$	18.5		$	13.5		$	26.7		$	20
	(In millions)	November 29, 2014			May 31, 2014
	Total Assets:
	North American Furniture Solutions	$	509		$	457
	ELA Furniture Solutions	238.4			244.8
	Specialty	155.7			157.7
	Consumer	219.5			18.8
	Corporate	71.3			112.6
	Total	$	1,193.90		$	990.9
	Total Goodwill:
	North American Furniture Solutions	$	135.8		$	135.8
	ELA Furniture Solutions	42.1			42.6
	Specialty	49.8			49.8
	Consumer	76.2			—
	Corporate	—			—
	Total	$	303.9		$	228.2

Subsequent_Event_Subsequent_Ev

Subsequent Event Subsequent Event	6 Months Ended
	Nov. 29, 2014
Subsequent Events [Abstract]
Subsequent Event Disclosure	SUBSEQUENT EVENT
	On January 3rd, 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. As of January 5th, 2015, the total debt outstanding related to borrowings against this facility was $126.2 million and the total usage against the facility was $136.8 million, of which $10.6 million related to outstanding letters of credit.

Inventories_Policies

Inventories (Policies)	6 Months Ended
	Nov. 29, 2014
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)	6 Months Ended
	Nov. 29, 2014
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)	6 Months Ended
	Nov. 29, 2014
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 November 29, 2014
	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
	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			1.3			239.9
	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			—			12.3
	Long term deferred tax liability	16.4			1.1			17.5
	Other long term liabilities	0.4			—			0.4
	Total liabilities assumed	52.1			1.1			53.2
	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 Design Within Reach 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			Six Months Ended
	(In millions)	July 28, 2014 - August 30, 2014			29-Nov-14			29-Nov-14
	DWR Net sales	$	21.6		$	66.8		$	88.4
	Intercompany sales elimination	(1.6		)	(5.8		)	(7.4		)
	Net sales impact to Herman Miller, Inc.	$	20		$	61		$	81
	Net loss	$	(1.6	)	$	(2.2	)	$	(3.8	)

Inventories_Tables

Inventories (Tables)	6 Months Ended
	Nov. 29, 2014
Inventories [Abstract]
Schedule of Inventory, Current
	(In millions)	29-Nov-14		31-May-14
	Finished goods	$	102.7	$	58.2
	Raw materials	23.6		20.2
	Total	$	126.3	$	78.4

Goodwill_and_Indefinitelived_I1

Goodwill and Indefinite-lived Intangibles (Tables)	6 Months Ended
	Nov. 29, 2014
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 November 29, 2014 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	(0.5		)	—		(0.5		)
	DWR acquisition	76.2			55.1		131.3
	November 29, 2014	$	303.9		$	96	$	399.9

Employee_Benefit_Plans_Tables

Employee Benefit Plans (Tables)	6 Months Ended
	Nov. 29, 2014
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
		November 29, 2014			November 30, 2013			November 29, 2014		November 30, 2013
	Domestic:
	Interest cost	$	—		$	2.6		$	0.1	$	0.1
	Expected return on plan assets	—			(1.9		)	—		—
	Net amortization loss	—			2.4			—		—
	Settlement loss recognized	—			158.2			—		—
	Net periodic benefit cost	$	—		$	161.3		$	0.1	$	0.1
	International:
	Interest cost	$	1.1		$	1
	Expected return on plan assets	(1.5		)	(1.2		)
	Net amortization loss	0.5			0.4
	Net periodic benefit cost	$	0.1		$	0.2
		Six Months Ended
		Pension Benefits						Other Post-Retirement Benefits
		29-Nov-14			30-Nov-13			29-Nov-14		30-Nov-13
	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	$	2.3		$	2
	Expected return on plan assets	(3.0		)	(2.4		)
	Net amortization loss	1			0.8
	Net periodic benefit cost	$	0.3		$	0.4

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	6 Months Ended
	Nov. 29, 2014
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					Six Months Ended
		November 29, 2014		November 30, 2013			November 29, 2014		November 30, 2013
	Numerators:
	Numerator for both basic and diluted EPS, net earnings - in millions	$	27.8	$	(80.6	)	$	53	$	(58.1	)
	Denominators:
	Denominator for basic EPS, weighted-average common shares outstanding	59,445,577		58,923,648			59,370,718		58,825,377
	Potentially dilutive shares resulting from stock plans	578,941		—			581,916		—
	Denominator for diluted EPS	60,024,518		58,923,648			59,952,634		58,825,377
	Antidilutive equity awards not included in weighted-average common shares - diluted	538,380		2,780,570			743,060		2,867,150

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	6 Months Ended
	Nov. 29, 2014
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 November 29, 2014 and May 31, 2014.
	(In millions)	Fair Value Measurements
		November 29, 2014		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	0.8		1.2
	Government obligations	4.9		7.9
	Mortgage-backed securities	0.6		1.6
	Foreign currency forward contracts	0.4		0.2
	Deferred compensation plan	7.2		6.3
	Total	$	14.2	$	17.6
	Financial Liabilities
	Foreign currency forward contracts	$	0.3	$	0.1
	Total	$	0.3	$	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.
		November 29, 2014
	(In millions)	Cost		Unrealized		Unrealized		Market
				Gain		Loss		Value
	Asset-backed securities	$	0.3	$	—	$	—	$	0.3
	Corporate securities	0.8		—		—		0.8
	Government obligations	4.9		—		—		4.9
	Mortgage-backed securities	0.6		—		—		0.6
	Total	$	6.6	$	—	$	—	$	6.6
		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 November 29, 2014, are as follows.
	(In millions)	Cost		Fair Value
	Due within one year	$	1.1	$	1.1
	Due after one year through five years	5.5		5.5
	Due after five years through ten years	—		—
	Total	$	6.6	$	6.6

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	6 Months Ended
	Nov. 29, 2014
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						Six Months Ended
		November 29, 2014			November 30, 2013			November 29, 2014			November 30, 2013
	Accrual Balance — beginning	$	25.7		$	24.6		$	25.2		$	24.8
	Accrual for warranty matters	6.2			5.4			12.7			10.3
	Settlements and adjustments	(5.9		)	(5.2		)	(11.9		)	(10.3		)
	Accrual Balance — ending	$	26		$	24.8		$	26		$	24.8

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Income (Loss) (Tables)	6 Months Ended
	Nov. 29, 2014
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 six months ended November 29, 2014 and November 30, 2013:
		Six Months Ended
	(In millions)	November 29, 2014			November 30, 2013
	Cumulative translation adjustments at beginning of period	$	(11.1	)	$	(14.0	)
	Translation adjustments	(5.9		)	2.1
	Balance at end of period	(17.0		)	(11.9		)
	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 $(0.2), $(35.7))	0.9			62
	Balance at end of period	(25.9		)	(22.7		)
	Total accumulated other comprehensive loss	$	(42.9	)	$	(34.6	)

Operating_Segments_Tables

Operating Segments (Tables)	6 Months Ended
	Nov. 29, 2014
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						Six Months Ended
	(In millions)	November 29, 2014			November 30, 2013			November 29, 2014			November 30, 2013
	Net Sales:
	North American Furniture Solutions	$	315.3		$	297.1		$	636.4		$	615.3
	ELA Furniture Solutions	114.3			103.1			209.7			184.7
	Specialty	55.4			53.2			110			105.2
	Consumer	80.4			17.1			119			33.4
	Corporate	—			—			—			—
	Total	$	565.4		$	470.5		$	1,075.10		$	938.6
	Depreciation and Amortization:
	North American Furniture Solutions	$	7		$	7.6		$	14.2		$	14.7
	ELA Furniture Solutions	2.2			1.4			4.4			3.4
	Specialty	1.8			1.3			3.5			3
	Consumer	2.1			0.2			3			0.5
	Corporate	0.1			—			0.1			—
	Total	$	13.2		$	10.5		$	25.2		$	21.6
	Operating Earnings:
	North American Furniture Solutions	$	32.3		$	(119.0	)	$	68.5		$	(85.0	)
	ELA Furniture Solutions	10.4			8.2			13.5			8.1
	Specialty	2.8			(8.9		)	5.7			(7.1		)
	Consumer	1.5			(1.3		)	3.8			2.1
	Corporate	(0.3		)	(4.2		)	(2.6		)	(4.2		)
	Total	$	46.7		$	(125.2	)	$	88.9		$	(86.1	)
	Capital Expenditures:
	North American Furniture Solutions	$	11.5		$	10.8		$	15.7		$	15.3
	ELA Furniture Solutions	4.4			1.2			6.3			2.6
	Specialty	1.1			1.5			2.2			2.1
	Consumer	1.5			—			2.5			—
	Corporate	—			—			—			—
	Total	$	18.5		$	13.5		$	26.7		$	20
	(In millions)	November 29, 2014			May 31, 2014
	Total Assets:
	North American Furniture Solutions	$	509		$	457
	ELA Furniture Solutions	238.4			244.8
	Specialty	155.7			157.7
	Consumer	219.5			18.8
	Corporate	71.3			112.6
	Total	$	1,193.90		$	990.9
	Total Goodwill:
	North American Furniture Solutions	$	135.8		$	135.8
	ELA Furniture Solutions	42.1			42.6
	Specialty	49.8			49.8
	Consumer	76.2			—
	Corporate	—			—
	Total	$	303.9		$	228.2

Fiscal_Year_Details

Fiscal Year (Details)	3 Months Ended		6 Months Ended
	Nov. 29, 2014	Nov. 30, 2013	Nov. 29, 2014	Nov. 30, 2013
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	3 Months Ended	4 Months Ended	6 Months Ended	0 Months Ended	5 Months Ended	0 Months Ended	3 Months Ended
In Millions, unless otherwise specified	Aug. 30, 2014	Nov. 29, 2014	Nov. 29, 2014	Nov. 29, 2014	Sep. 30, 2013	Mar. 01, 2014	Jul. 28, 2014	Nov. 30, 2013	Aug. 31, 2013	31-May-14
								dealerships	dealerships
Business Acquisition
Long-term Line of Credit							$127
Goodwill		303.9	303.9	303.9						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		0.2		2.2
Goodwill		76.2	76.2	76.2
Other intangible assets		69.3	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

Acquisitions_and_Divestitures_2

Acquisitions and Divestitures - Schedule of Business Acquisitions, by Acquisition (Details) (USD $)	4 Months Ended	1 Months Ended	3 Months Ended
In Millions, unless otherwise specified	Nov. 29, 2014	Aug. 30, 2014	Nov. 29, 2014	31-May-14
Fair value of the assets acquired:
Goodwill	$303.90		$303.90	$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
Other current assets	5.5		5.5
Long term deferred tax asset	3.7		3.7
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	239.9		239.9
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		12.3
Long term deferred tax liability	17.5		17.5
Other long term liabilities	0.4		0.4
Total liabilities assumed	53.2		53.2
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
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
Other current assets	0		0
Long term deferred tax asset	0		0
Goodwill	1.8		1.8
Other intangible assets	-0.3		-0.3
Property	0		0
Other long term assets	0		0
Total assets acquired	1.3		1.3
Fair value of liabilities assumed:
Accounts payable	0		0
Current deferred tax liabilities	0		0
Accrued compensation and benefits	0		0
Other accrued liabilities	0		0
Long term deferred tax liability	1.1		1.1
Other long term liabilities	0		0
Total liabilities assumed	1.1		1.1
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 $)	6 Months Ended	4 Months Ended
In Millions, unless otherwise specified	Nov. 29, 2014	Nov. 29, 2014
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		6 Months Ended		1 Months Ended	4 Months Ended
In Millions, unless otherwise specified	Nov. 29, 2014	Nov. 30, 2013	Nov. 29, 2014	Nov. 30, 2013	Aug. 30, 2014	Nov. 29, 2014
Business Acquisition
Net sales	$565.40	$470.50	$1,075.10	$938.60
Design Within Reach
Business Acquisition
Net sales	66.8				21.6	88.4
Net sales impact to Herman Miller, Inc.	61				20	81
Net loss	-2.2				-1.6	-3.8
Intercompany Segment Eliminations | Design Within Reach
Business Acquisition
Net sales	($5.80)				($1.60)	($7.40)

Acquisitions_and_Divestitures_4

Acquisitions and Divestitures - Phantom (Details) (Customer Relationships, Design Within Reach)	4 Months Ended
	Nov. 29, 2014
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 $)	Nov. 29, 2014	31-May-14
In Millions, unless otherwise specified
Inventories [Abstract]
Finished goods	$102.70	$58.20
Raw materials	23.6	20.2
Total	$126.30	$78.40

Goodwill_and_Indefinitelived_I2

Goodwill and Indefinite-lived Intangibles (Details) (USD $)	6 Months Ended
In Millions, unless otherwise specified	Nov. 29, 2014
Goodwill [Roll Forward]
Goodwill, beginning	$228.20
Foreign currency translation adjustments	-0.5
DWR acquisition	76.2
Goodwill, ending	303.9
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	-0.5
DWR acquisition	131.3
Goodwill and indefinite-lived intangibles, ending	$399.90

Employee_Benefit_Plans_Details

Employee Benefit Plans (Details) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Nov. 29, 2014	Nov. 30, 2013	Nov. 29, 2014	Nov. 30, 2013
United States Pension Plan of US Entity
Defined Benefit Plan Disclosure
Interest cost	$0	$2.60	$0	$5.20
Expected return on plan assets	0	-1.9	0	-3.8
Net amortization loss	0	2.4	0	4.8
Net periodic benefit cost	0	161.3	0	164.4
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements	0	158.2	0	158.2
Foreign Pension Plan
Defined Benefit Plan Disclosure
Interest cost	1.1	1	2.3	2
Expected return on plan assets	-1.5	-1.2	-3	-2.4
Net amortization loss	0.5	0.4	1	0.8
Net periodic benefit cost	0.1	0.2	0.3	0.4
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		6 Months Ended
	Nov. 29, 2014	Nov. 30, 2013	Nov. 29, 2014	Nov. 30, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive equity awards not included in weighted-average common shares	538,380	2,780,570	743,060	2,867,150
Equity Option
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive equity awards not included in weighted-average common shares	507,252	2,094,277	716,843	2,191,741

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		6 Months Ended
In Millions, except Share data, unless otherwise specified	Nov. 29, 2014	Nov. 30, 2013	Nov. 29, 2014	Nov. 30, 2013
Earnings Per Share [Abstract]
Numerator for both basic and diluted EPS, net earnings - in millions	$27.80	($80.60)	$53	($58.10)
Denominator for basic EPS, weighted-average common shares outstanding	59,445,577	58,923,648	59,370,718	58,825,377
Potentially dilutive shares resulting from stock plans	578,941	0	581,916	0
Denominator for diluted EPS	60,024,518	58,923,648	59,952,634	58,825,377
Antidilutive equity awards not included in weighted-average common shares - diluted	538,380	2,780,570	743,060	2,867,150

StockBased_Compensation_Detail

Stock-Based Compensation (Details) (USD $)	3 Months Ended		6 Months Ended
In Millions, except Share data, unless otherwise specified	Nov. 29, 2014	Nov. 30, 2013	Nov. 29, 2014	Nov. 30, 2013
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Allocated Share-based Compensation Expense	$2.70	$2.80	$5.70	$5.60
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	$1	$1	$2.10	$2
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period			226,867	390,080
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			121,985	93,041
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		6 Months Ended
In Millions, unless otherwise specified	Nov. 29, 2014	Nov. 30, 2013	Nov. 29, 2014	Nov. 30, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	$1	$1	$2.10	$2

Income_Taxes_Details

Income Taxes (Details) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Nov. 29, 2014	Nov. 30, 2013	Nov. 29, 2014	Nov. 30, 2013
Income Tax Disclosure [Abstract]
Effective Income Tax Rate, Continuing Operations	33.80%	37.60%	33.40%	38.70%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			35.00%
Liability for Uncertain Tax Positions, Current	$1.40	$1.40	$1.40	$1.40
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	0	0	0.1	0.1
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	$0.70	$0.60	$0.70	$0.60

Income_Taxes_Phantom_Details

Income Taxes - Phantom (Details) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Nov. 29, 2014	Nov. 30, 2013	Nov. 29, 2014	Nov. 30, 2013
Income Tax Disclosure [Abstract]
Liability for Uncertain Tax Positions, Current	$1.40	$1.40	$1.40	$1.40
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	0.7	0.6	0.7	0.6
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	$0	$0	$0.10	$0.10

Fair_Value_Measurements_Fair_V

Fair Value Measurements - Fair Value Hierarchy (Details) (Fair Value, Inputs, Level 2, Fair Value, Measurements, Recurring, USD $)	Nov. 29, 2014	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	$7.20	$6.30
Assets, Fair Value Disclosure	14.2	17.6
Financial and Nonfinancial Liabilities, Fair Value Disclosure	0.3	0.1
Foreign Exchange Forward
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Foreign Currency Contract, Asset, Fair Value Disclosure	0.4	0.2
Foreign Currency Contracts, Liability, Fair Value Disclosure	0.3	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	0.8	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	$0.60	$1.60

Fair_Value_Measurements_Unreal

Fair Value Measurements - Unrealized Gain (Loss) on Investments (Details) (USD $)	Nov. 29, 2014	31-May-14
In Millions, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cost	$6.60	$11.10
Unrealized Gain	0	0
Unrealized Loss	0	0
Market Value	6.6	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	0.8	1.2
Unrealized Gain	0	0
Unrealized Loss	0	0
Market Value	0.8	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	0.6	1.6
Unrealized Gain	0	0
Unrealized Loss	0	0
Market Value	$0.60	$1.60

Fair_Value_Measurements_Maturi

Fair Value Measurements - Maturities of Available-for-sale marketable securities (Details) (USD $)	Nov. 29, 2014	31-May-14
In Millions, unless otherwise specified
Fair Value Disclosures [Abstract]
Available-for-sale Securities, Debt Maturities, within One Year, Amortized Cost Basis	$1.10
Available-for-sale Securities, Debt Maturities, within One Year, Fair Value	1.1
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Amortized Cost Basis	5.5
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Fair Value	5.5
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, Amortized Cost Basis	$6.60	$11.10

Commitments_and_Contingencies_1

Commitments and Contingencies (Details) (USD $)	6 Months Ended
In Millions, unless otherwise specified	Nov. 29, 2014	31-May-14
Schedule of Warranty Accrual
Warranty Length	12 years
Performance Guarantee
Schedule of Warranty Accrual
Guarantor Obligations, Maximum Exposure, Undiscounted	10.4
Guarantor Obligations, Current Carrying Value	0	0
Financial Standby Letter of Credit
Schedule of Warranty Accrual
Guarantor Obligations, Maximum Exposure, Undiscounted	10.6
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		6 Months Ended
In Millions, unless otherwise specified	Nov. 29, 2014	Nov. 30, 2013	Nov. 29, 2014	Nov. 30, 2013
Movement in Standard Product Warranty Accrual [Roll Forward]
Accrual Balance — beginning	$25.70	$24.60	$25.20	$24.80
Accrual for warranty matters	6.2	5.4	12.7	10.3
Settlements and adjustments	-5.9	-5.2	-11.9	-10.3
Accrual Balance — ending	$26	$24.80	$26	$24.80

Commitments_and_Contingencies_3

Commitments and Contingencies - Phantom (Details) (USD $)	Nov. 29, 2014	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 $)	Nov. 29, 2014	Jul. 28, 2014	31-May-14
In Millions, unless otherwise specified
Line of Credit Facility
Current maturities of long-term debt	$50		$50
Long-term Line of Credit		127
Borrowings on revolver and outstanding letters of credit	87.6
Letters of Credit Outstanding, Amount			4.9
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	77
Letters of Credit Outstanding, Amount	10.6
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	Nov. 29, 2014	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		6 Months Ended
In Millions, unless otherwise specified	Nov. 29, 2014	Nov. 30, 2013	Nov. 29, 2014	Nov. 30, 2013	31-May-14
Cumulative translation adjustments [Roll Forward]
Cumulative translation adjustments at beginning of period			($11.10)	($14)
Translation adjustments	-5.4	2.8	-5.9	2.1
Balance at end of period	-17	-11.9	-17	-11.9
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	-25.9	-22.7	-25.9	-22.7
Total accumulated other comprehensive loss	-42.9	-34.6	-42.9	-34.6	-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			0.9	62
Reclassification Adjustment from AOCI, Pension and Other Postretirement Plans, Tax			($0.20)	($35.70)

Restructuring_Activities_Detai

Restructuring Activities (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Nov. 30, 2013
Restructuring and Related Activities [Abstract]
Tangible Asset Impairment Charges	$4

Operating_Segments_Details

Operating Segments (Details) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Nov. 29, 2014	Nov. 30, 2013	Nov. 29, 2014	Nov. 30, 2013	31-May-14
Segment Reporting Information
Net Sales:	$565.40	$470.50	$1,075.10	$938.60
Depreciation and Amortization:	13.2	10.5	25.2	21.6
Operating Earnings:	46.7	-125.2	88.9	-86.1
Capital Expenditures:	18.5	13.5	26.7	20
Total Assets:	1,193.90		1,193.90		990.9
Total Goodwill:	303.9		303.9		228.2
North American Furniture Solutions
Segment Reporting Information
Net Sales:	315.3	297.1	636.4	615.3
Depreciation and Amortization:	7	7.6	14.2	14.7
Operating Earnings:	32.3	-119	68.5	-85
Capital Expenditures:	11.5	10.8	15.7	15.3
Total Assets:	509		509		457
Total Goodwill:	135.8		135.8		135.8
ELA Furniture Solutions
Segment Reporting Information
Net Sales:	114.3	103.1	209.7	184.7
Depreciation and Amortization:	2.2	1.4	4.4	3.4
Operating Earnings:	10.4	8.2	13.5	8.1
Capital Expenditures:	4.4	1.2	6.3	2.6
Total Assets:	238.4		238.4		244.8
Total Goodwill:	42.1		42.1		42.6
Specialty
Segment Reporting Information
Net Sales:	55.4	53.2	110	105.2
Depreciation and Amortization:	1.8	1.3	3.5	3
Operating Earnings:	2.8	-8.9	5.7	-7.1
Capital Expenditures:	1.1	1.5	2.2	2.1
Total Assets:	155.7		155.7		157.7
Total Goodwill:	49.8		49.8		49.8
Consumer
Segment Reporting Information
Net Sales:	80.4	17.1	119	33.4
Depreciation and Amortization:	2.1	0.2	3	0.5
Operating Earnings:	1.5	-1.3	3.8	2.1
Capital Expenditures:	1.5	0	2.5	0
Total Assets:	219.5		219.5		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	0.1	0
Operating Earnings:	-0.3	-4.2	-2.6	-4.2
Capital Expenditures:	0	0	0	0
Total Assets:	71.3		71.3		112.6
Total Goodwill:	$0		$0		$0

Subsequent_Event_Subsequent_Ev1

Subsequent Event Subsequent Event (Details) (USD $)	0 Months Ended
In Millions, unless otherwise specified	Jan. 03, 2015	Nov. 29, 2014	Jul. 28, 2014	31-May-14	Jan. 05, 2015
Subsequent Event [Line Items]
Long-term Line of Credit			$127
Long-term Line of Credit, Noncurrent		87.6
Letters of Credit Outstanding, Amount				4.9
Extinguishment of Debt, Type [Domain]
Subsequent Event [Line Items]
Repayments of Debt	50
Revolving Line of Credit, Domestic [Member]
Subsequent Event [Line Items]
Long-term Line of Credit		77
Letters of Credit Outstanding, Amount		10.6
Revolving Line of Credit, Domestic [Member] | Extinguishment of Debt, Type [Domain]
Subsequent Event [Line Items]
Long-term Line of Credit					126.2
Long-term Line of Credit, Noncurrent					136.8
Letters of Credit Outstanding, Amount					$10.60