CONSOLIDATED STATEMENTS OF EARNINGS (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
NET SALES	$ 1,094.4us-gaap_SalesRevenueGoodsNet	$ 1,113.3us-gaap_SalesRevenueGoodsNet
Cost of Products Sold	393.5us-gaap_CostOfGoodsSold	405.7us-gaap_CostOfGoodsSold
GROSS PROFIT	700.9us-gaap_GrossProfit	707.6us-gaap_GrossProfit
Expenses:
Selling, General and Administrative	233.2	232.9
Advertising and Promotion	144.4us-gaap_MarketingAndAdvertisingExpense	155.7us-gaap_MarketingAndAdvertisingExpense
Research and Development	25.9us-gaap_ResearchAndDevelopmentExpense	27.1us-gaap_ResearchAndDevelopmentExpense
Other Expenses—net	12.2mjn_OtherExpensesincomenet	0.7mjn_OtherExpensesincomenet
EARNINGS BEFORE INTEREST AND INCOME TAXES	285.2	291.2
Interest Expense-net	13.8	12.4
EARNINGS BEFORE INCOME TAXES	271.4	278.8
Provision for Income Taxes	64.3us-gaap_IncomeTaxExpenseBenefit	71.0us-gaap_IncomeTaxExpenseBenefit
NET EARNINGS	207.1us-gaap_ProfitLoss	207.8us-gaap_ProfitLoss
Less Net Earnings/(Loss) Attributable to Noncontrolling Interests	(0.3)	5.4
NET EARNINGS ATTRIBUTABLE TO SHAREHOLDERS	$ 207.4us-gaap_NetIncomeLoss	$ 202.4us-gaap_NetIncomeLoss
Earnings per Share-Basic
Net Earnings Attributable to Shareholders (in dollars per share)	$ 1.02us-gaap_EarningsPerShareBasic	$ 1.00us-gaap_EarningsPerShareBasic
Earnings per Share-Diluted
Net Earnings Attributable to Shareholders (in dollars per share)	$ 1.02us-gaap_EarningsPerShareDiluted	$ 1.00us-gaap_EarningsPerShareDiluted
Weighted Average Shares - Basic	202.4	201.9
Weighted Average Shares - Diluted	202.9	202.4
Dividends Declared per Share (in dollars per share)	$ 0.4125	$ 0.3750

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Aggregate dividends declared during the period for each share of common stock outstanding.

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Total costs related to goods produced and sold during the reporting period.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The net amount of nonoperating interest income (expense).

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The total expense recognized in the period for promotion, public relations, and brand or product advertising.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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