XML 131 R113.htm IDEA: XBRL DOCUMENT v3.4.0.3

Pension Benefits - Summary Of Pension Plan Assets Using Fair Value Hierarchy By Asset Class (Details) - USD ($) $ in Millions	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 262	$ 298	$ 300
U.S. Plans | Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	262	298
U.S. Plans | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4	56
U.S. Plans | Common and preferred stock
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	16	18
U.S. Plans | Equity commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	165	138
U.S. Plans | Government securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12	14
U.S. Plans | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12	14
U.S. Plans | Mortgage-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	14	14
U.S. Plans | Asset-backed securities and other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	22	26
U.S. Plans | Fixed income commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Real estate funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	17	18
U.S. Plans | Other commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
U.S. Plans | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 1 | Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	20	73
U.S. Plans | Level 1 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4	55
U.S. Plans | Level 1 | Common and preferred stock
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	16	18
U.S. Plans | Level 1 | Equity commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 1 | Government securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 1 | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 1 | Mortgage-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 1 | Asset-backed securities and other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 1 | Fixed income commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 1 | Real estate funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 1 | Other commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
U.S. Plans | Level 1 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 2 | Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	225	207
U.S. Plans | Level 2 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	1
U.S. Plans | Level 2 | Common and preferred stock
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 2 | Equity commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	165	138
U.S. Plans | Level 2 | Government securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12	14
U.S. Plans | Level 2 | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12	14
U.S. Plans | Level 2 | Mortgage-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	14	14
U.S. Plans | Level 2 | Asset-backed securities and other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	22	26
U.S. Plans | Level 2 | Fixed income commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 2 | Real estate funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 2 | Other commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
U.S. Plans | Level 2 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	17	18	16
U.S. Plans | Level 3 | Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	17	18
U.S. Plans | Level 3 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 3 | Common and preferred stock
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 3 | Equity commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 3 | Government securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 3 | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 3 | Mortgage-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 3 | Asset-backed securities and other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 3 | Fixed income commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. Plans | Level 3 | Real estate funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	17	18	16
U.S. Plans | Level 3 | Other commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
U.S. Plans | Level 3 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	607	612	590
Non-U.S. Plans | Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	607	612
Non-U.S. Plans | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4	8
Non-U.S. Plans | Common and preferred stock
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Equity commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	156	156
Non-U.S. Plans | Government securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	91	79
Non-U.S. Plans | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	15	13
Non-U.S. Plans | Mortgage-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Asset-backed securities and other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Fixed income commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	186	191
Non-U.S. Plans | Real estate funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	24	26
Non-U.S. Plans | Other commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		13
Non-U.S. Plans | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	131	126
Non-U.S. Plans | Level 1 | Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	121	112
Non-U.S. Plans | Level 1 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4	8
Non-U.S. Plans | Level 1 | Common and preferred stock
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Level 1 | Equity commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6	7
Non-U.S. Plans | Level 1 | Government securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	23	26
Non-U.S. Plans | Level 1 | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1	0
Non-U.S. Plans | Level 1 | Mortgage-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Level 1 | Asset-backed securities and other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Level 1 | Fixed income commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	66	64
Non-U.S. Plans | Level 1 | Real estate funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Level 1 | Other commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
Non-U.S. Plans | Level 1 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	21	7
Non-U.S. Plans | Level 2 | Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	459	470
Non-U.S. Plans | Level 2 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Level 2 | Common and preferred stock
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Level 2 | Equity commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	150	149
Non-U.S. Plans | Level 2 | Government securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	68	53
Non-U.S. Plans | Level 2 | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	14	13
Non-U.S. Plans | Level 2 | Mortgage-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Level 2 | Asset-backed securities and other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Level 2 | Fixed income commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	120	127
Non-U.S. Plans | Level 2 | Real estate funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Level 2 | Other commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		13
Non-U.S. Plans | Level 2 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	107	115
Non-U.S. Plans | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	27	30	12
Non-U.S. Plans | Level 3 | Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	27	30
Non-U.S. Plans | Level 3 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Level 3 | Common and preferred stock
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Level 3 | Equity commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Level 3 | Government securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Level 3 | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Level 3 | Mortgage-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Level 3 | Asset-backed securities and other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Level 3 | Fixed income commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Non-U.S. Plans | Level 3 | Real estate funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	24	26	$ 7
Non-U.S. Plans | Level 3 | Other commingled funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
Non-U.S. Plans | Level 3 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 3	$ 4

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedBenefitPlanDisclosureLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 30
-Section 35
-Paragraph 50
-URI http://asc.fasb.org/extlink&oid=49178875&loc=d3e12355-114930

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

+ Details

Name:	us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

Name:	us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_InvestmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_CashAndCashEquivalentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_EquitySecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_EquityFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_USGovernmentAgenciesDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_MortgageBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_AssetBackedSecuritiesSecuritizedLoansAndReceivablesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_FixedIncomeFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_RealEstateFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=mck_OtherCommingledFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=mck_OtherfundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=us-gaap_ForeignPensionPlansDefinedBenefitMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: