ACCOUNTING POLICIES (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenue Recognition
WIC rebate accruals	$ 214.3mjn_AccruedWICRebates	$ 199.7mjn_AccruedWICRebates
Reduction in revenue due to rebates under the WIC program	790.0mjn_ReductionInRevenueDueToWICRebates	702.3mjn_ReductionInRevenueDueToWICRebates	730.0mjn_ReductionInRevenueDueToWICRebates
Sales return accruals	47.0mjn_AccruedSalesReturn	44.8mjn_AccruedSalesReturn
Reduction in sales due to sales returns	86.1mjn_ReductionInSalesDueToReturns	81.0mjn_ReductionInSalesDueToReturns	82.5mjn_ReductionInSalesDueToReturns
Cash and Cash Equivalents
Maximum Term of Original Maturity to Classify Instruments as Cash and Cash Equivalents(months)	3 months
Money market funds, classified as Level Two	$ 395.4us-gaap_MoneyMarketFundsAtCarryingValue	$ 447.8us-gaap_MoneyMarketFundsAtCarryingValue

Represents sales return accruals which are included in accrued rebates and returns on the Balance Sheet.

No definition available.

Name:	mjn_AccruedSalesReturn
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Represents accruals for Women, Infants and Children (WIC) rebates which are included in accrued rebates and returns on the Balance Sheet.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the maximum period for maturity of cash and cash equivalents.

+ References

No definition available.

+ Details

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Namespace Prefix:	mjn_
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Balance Type:	na
Period Type:	duration

- Definition

Represents the reduction in revenue due to rebates under the Women, Infants and Children (WIC) program.

+ References

No definition available.

+ Details

Name:	mjn_ReductionInRevenueDueToWICRebates
Namespace Prefix:	mjn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the reduction in sales due to sales returns.

+ References

No definition available.

+ Details

Name:	mjn_ReductionInSalesDueToReturns
Namespace Prefix:	mjn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_CashAndCashEquivalentsAbstract
Namespace Prefix:	us-gaap_
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- Definition

Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

+ Details

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Balance Type:	debit
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- Details

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