XML 80 R94.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Debt and Financing Activities (Long-Term Debt) (Narrative) (Details) (USD $) In Millions, unless otherwise specified | 0 Months Ended | 1 Months Ended | 12 Months Ended
--- | --- | --- | ---
Mar. 05, 2014 | Dec. 04, 2012 | Mar. 31, 2013 | Mar. 31, 2015 D | Mar. 31, 2014 | Mar. 31, 2013
Debt Instrument [Line Items] |  |  |  |  |  |
Proceeds from issuances of long-term debt | $ 4,068us-gaap_ProceedsFromIssuanceOfLongTermDebt | $ 892us-gaap_ProceedsFromIssuanceOfLongTermDebt | $ 891us-gaap_ProceedsFromIssuanceOfLongTermDebt | $ 3us-gaap_ProceedsFromIssuanceOfLongTermDebt | $ 4,124us-gaap_ProceedsFromIssuanceOfLongTermDebt | $ 1,798us-gaap_ProceedsFromIssuanceOfLongTermDebt
Days notice for redemption prior to maturity |  |  |  | 30mck_NumberOfDaysNoticeBeforeNotesCanBeRedeemed |  |
Redemption purchase offer |  |  |  | 101.00%mck_ContingentPurchaseOfferSeries |  |
Long-term debt |  |  |  | 9,709us-gaap_LongTermDebt | 10,346us-gaap_LongTermDebt |
Future principal payments of long-term debt in 2016 |  |  |  |  | 1,529us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths |
Future principal payments of long-term debt in 2017 |  |  |  |  | 1,619us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo |
Future principal payments of long-term debt in 2018 |  |  |  |  | 1,086us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree |
Future principal payments of long-term debt in 2019 |  |  |  |  | 1,474us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour |
Future principal payments of long-term debt in 2020 |  |  |  |  | 19us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive |
Future principal payments of long-term debt, thereafter |  |  |  |  | 3,982us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive |
Floating Rate Notes Due September 10, 2015 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt face value |  |  |  |  | 400us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = mck_FloatingRateNotesDueSeptemberTenthTwoThousandFifteenMember |
Debt variable interest rate |  |  |  | 0.66%us-gaap_LongTermDebtPercentageBearingVariableInterestRate / us-gaap_LongtermDebtTypeAxis = mck_FloatingRateNotesDueSeptemberTenthTwoThousandFifteenMember |  |
Debt maturity date |  |  |  | Sep. 10, 2015 | Sep. 10, 2015 |
Long-term debt |  |  |  | 400us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_FloatingRateNotesDueSeptemberTenthTwoThousandFifteenMember | 400us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_FloatingRateNotesDueSeptemberTenthTwoThousandFifteenMember |
1.29% Notes Due March 10, 2017 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt face value |  |  |  |  | 700us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = mck_OnePointTwoNinePercentNotesDueMarchTenthTwoThousandSeventeenMember |
Debt interest rate |  |  |  | 1.29%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_OnePointTwoNinePercentNotesDueMarchTenthTwoThousandSeventeenMember | 1.29%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_OnePointTwoNinePercentNotesDueMarchTenthTwoThousandSeventeenMember |
Debt maturity date |  |  |  | Mar. 10, 2017 | Mar. 10, 2017 |
Long-term debt |  |  |  | 700us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_OnePointTwoNinePercentNotesDueMarchTenthTwoThousandSeventeenMember | 700us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_OnePointTwoNinePercentNotesDueMarchTenthTwoThousandSeventeenMember |
2.28% Notes Due March 15, 2019 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt face value |  |  |  |  | 1,100us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = mck_TwoPointTwoEightNotesDueMarchFifteenthTwoThousandNineteenMember |
Debt interest rate |  |  |  | 2.28%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_TwoPointTwoEightNotesDueMarchFifteenthTwoThousandNineteenMember | 2.28%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_TwoPointTwoEightNotesDueMarchFifteenthTwoThousandNineteenMember |
Debt maturity date |  |  |  | Mar. 15, 2019 | Mar. 15, 2019 |
Long-term debt |  |  |  | 1,100us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_TwoPointTwoEightNotesDueMarchFifteenthTwoThousandNineteenMember | 1,100us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_TwoPointTwoEightNotesDueMarchFifteenthTwoThousandNineteenMember |
3.80% Notes Due March 15, 2024 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt face value |  |  |  |  | 1,100us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = mck_ThreePointEightZeroPercentNotesDueMarchFifteenthTwoThousandTwentyFourMember |
Debt interest rate |  |  |  | 3.80%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_ThreePointEightZeroPercentNotesDueMarchFifteenthTwoThousandTwentyFourMember | 3.80%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_ThreePointEightZeroPercentNotesDueMarchFifteenthTwoThousandTwentyFourMember |
Debt maturity date |  |  |  | Mar. 15, 2024 | Mar. 15, 2024 |
Long-term debt |  |  |  | 1,100us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_ThreePointEightZeroPercentNotesDueMarchFifteenthTwoThousandTwentyFourMember | 1,100us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_ThreePointEightZeroPercentNotesDueMarchFifteenthTwoThousandTwentyFourMember |
4.88% Notes Due March 15, 2044 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt face value |  |  |  |  | 800us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = mck_FourPointEightEightPercentNotesDueMarchFifteenthTwoThousandFortyFourMember |
Debt interest rate |  |  |  | 4.88%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_FourPointEightEightPercentNotesDueMarchFifteenthTwoThousandFortyFourMember | 4.88%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_FourPointEightEightPercentNotesDueMarchFifteenthTwoThousandFortyFourMember |
Debt maturity date |  |  |  | Mar. 15, 2044 | Mar. 15, 2044 |
Long-term debt |  |  |  | 800us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_FourPointEightEightPercentNotesDueMarchFifteenthTwoThousandFortyFourMember | 800us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_FourPointEightEightPercentNotesDueMarchFifteenthTwoThousandFortyFourMember |
1.40% Notes Due March 15, 2018 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt face value |  |  | 500us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = mck_OnePointFourZeroPercentNotesDueMarchFifteenthTwoThousandEighteenMember |  |  | 500us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = mck_OnePointFourZeroPercentNotesDueMarchFifteenthTwoThousandEighteenMember
Debt interest rate |  |  | 1.40%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_OnePointFourZeroPercentNotesDueMarchFifteenthTwoThousandEighteenMember | 1.40%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_OnePointFourZeroPercentNotesDueMarchFifteenthTwoThousandEighteenMember | 1.40%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_OnePointFourZeroPercentNotesDueMarchFifteenthTwoThousandEighteenMember | 1.40%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_OnePointFourZeroPercentNotesDueMarchFifteenthTwoThousandEighteenMember
Debt maturity date |  |  |  | Mar. 15, 2018 | Mar. 15, 2018 | Mar. 15, 2018
Long-term debt |  |  |  | 499us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_OnePointFourZeroPercentNotesDueMarchFifteenthTwoThousandEighteenMember | 499us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_OnePointFourZeroPercentNotesDueMarchFifteenthTwoThousandEighteenMember |
2.85% Notes Due March 15, 2023 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt face value |  |  | 400us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = mck_TwoPointEightFivePercentNotesDueMarchFifteenTwoThousandTwentyThreeMember |  |  | 400us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = mck_TwoPointEightFivePercentNotesDueMarchFifteenTwoThousandTwentyThreeMember
Debt interest rate |  |  | 2.85%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_TwoPointEightFivePercentNotesDueMarchFifteenTwoThousandTwentyThreeMember | 2.85%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_TwoPointEightFivePercentNotesDueMarchFifteenTwoThousandTwentyThreeMember | 2.85%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_TwoPointEightFivePercentNotesDueMarchFifteenTwoThousandTwentyThreeMember | 2.85%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_TwoPointEightFivePercentNotesDueMarchFifteenTwoThousandTwentyThreeMember
Debt maturity date |  |  |  | Mar. 15, 2023 | Mar. 15, 2023 | Mar. 15, 2023
Long-term debt |  |  |  | 400us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_TwoPointEightFivePercentNotesDueMarchFifteenTwoThousandTwentyThreeMember | 400us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_TwoPointEightFivePercentNotesDueMarchFifteenTwoThousandTwentyThreeMember |
0.95% Notes Due December 4, 2015 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt face value |  |  | 500us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = mck_ZeroPointNineFivePercentNotesDueDecemberFourTwoThousandFifteenMember |  |  | 500us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = mck_ZeroPointNineFivePercentNotesDueDecemberFourTwoThousandFifteenMember
Debt interest rate |  |  | 0.95%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_ZeroPointNineFivePercentNotesDueDecemberFourTwoThousandFifteenMember | 0.95%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_ZeroPointNineFivePercentNotesDueDecemberFourTwoThousandFifteenMember | 0.95%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_ZeroPointNineFivePercentNotesDueDecemberFourTwoThousandFifteenMember | 0.95%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_ZeroPointNineFivePercentNotesDueDecemberFourTwoThousandFifteenMember
Debt maturity date |  |  |  | Dec. 04, 2015 | Dec. 04, 2015 | Dec. 04, 2015
Long-term debt |  |  |  | 500us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_ZeroPointNineFivePercentNotesDueDecemberFourTwoThousandFifteenMember | 499us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_ZeroPointNineFivePercentNotesDueDecemberFourTwoThousandFifteenMember |
2.70% Notes Due December 15, 2022 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt face value |  |  | 400us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = mck_TwoPointSevenZeroPercentNotesDueDecemberFifteenTwoThousandTwentyTwoMember |  |  | 400us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = mck_TwoPointSevenZeroPercentNotesDueDecemberFifteenTwoThousandTwentyTwoMember
Debt interest rate |  |  | 2.70%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_TwoPointSevenZeroPercentNotesDueDecemberFifteenTwoThousandTwentyTwoMember | 2.70%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_TwoPointSevenZeroPercentNotesDueDecemberFifteenTwoThousandTwentyTwoMember | 2.70%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_TwoPointSevenZeroPercentNotesDueDecemberFifteenTwoThousandTwentyTwoMember | 2.70%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_TwoPointSevenZeroPercentNotesDueDecemberFifteenTwoThousandTwentyTwoMember
Debt maturity date |  |  |  | Dec. 15, 2022 | Dec. 15, 2022 | Dec. 15, 2022
Long-term debt |  |  |  | 400us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_TwoPointSevenZeroPercentNotesDueDecemberFifteenTwoThousandTwentyTwoMember | 400us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_TwoPointSevenZeroPercentNotesDueDecemberFifteenTwoThousandTwentyTwoMember |
6.50% Notes Due February 15, 2014 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt interest rate |  |  |  |  | 6.50%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_SixPointFiveZeroPercentNotesDueFebruaryFifteenTwoThousandFourteenMember |
Debt repayment amount |  |  |  |  | 350us-gaap_RepaymentsOfDebt / us-gaap_LongtermDebtTypeAxis = mck_SixPointFiveZeroPercentNotesDueFebruaryFifteenTwoThousandFourteenMember |
5.25% Notes Due March 1, 2013 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt interest rate |  |  |  |  | 5.25%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_FivePointTwoFivePercentNotesDueMarchOneTwoThousandThirteenMember |
Debt repayment amount |  |  |  |  | 500us-gaap_RepaymentsOfDebt / us-gaap_LongtermDebtTypeAxis = mck_FivePointTwoFivePercentNotesDueMarchOneTwoThousandThirteenMember |
4.00% Bonds Due October 18, 2016 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt interest rate |  |  |  | 4.00%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_FourPercentBondsDueOctoberEighteenTwoThousandSixteenMember | 4.00%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_FourPercentBondsDueOctoberEighteenTwoThousandSixteenMember |
Debt maturity date |  |  |  | Oct. 18, 2016 | Oct. 18, 2016 |
Long-term debt |  |  |  | 388us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_FourPercentBondsDueOctoberEighteenTwoThousandSixteenMember | 507us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_FourPercentBondsDueOctoberEighteenTwoThousandSixteenMember |
4.50% Bonds Due April 26, 2017 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt interest rate |  |  |  | 4.50%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_FourPointFivePercentBondsDueAprilTwentySixTwoThousandSeventeenMember | 4.50%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_FourPointFivePercentBondsDueAprilTwentySixTwoThousandSeventeenMember |
Debt maturity date |  |  |  | Apr. 26, 2017 | Apr. 26, 2017 |
Long-term debt |  |  |  | 563us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_FourPointFivePercentBondsDueAprilTwentySixTwoThousandSeventeenMember | 737us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_FourPointFivePercentBondsDueAprilTwentySixTwoThousandSeventeenMember |
4.00% Bonds Due October 18, 2016 and 4.50% Bonds Due April 26, 2017 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt |  |  |  | 951us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_A4.00BondsDueOctober182016and4.50BondsDueApril262017Member | 1,244us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_A4.00BondsDueOctober182016and4.50BondsDueApril262017Member |
Promissory Notes [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt |  |  |  | 0us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_PromissoryNotesMember | 297us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_PromissoryNotesMember |
Term Loan [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt variable interest rate |  |  |  | 1.93%us-gaap_LongTermDebtPercentageBearingVariableInterestRate / us-gaap_LongtermDebtTypeAxis = mck_TermLoanMember |  |
Debt maturity date |  |  |  | Dec. 15, 2019 |  |
Long-term debt |  |  |  | 89us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_TermLoanMember | 100us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = mck_TermLoanMember |
Senior Notes Due 2022 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt interest rate |  |  | 6.375%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_SeniorNotesDue2022Member |  |  | 6.375%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_SeniorNotesDue2022Member
Debt maturity date |  |  |  |  |  | Jan. 31, 2022
Senior Convertible Notes Due 2014 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt interest rate |  |  |  | 3.125%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = mck_SeniorConvertibleNotesDue2014Member |  |
Debt maturity date |  |  |  |  |  | Nov. 30, 2014
Senior Notes Due 2022 And Senior Convertible Notes Due 2014 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt repayment amount |  |  |  |  |  | $ 643us-gaap_RepaymentsOfDebt / us-gaap_LongtermDebtTypeAxis = mck_SeniorNotesDue2022AndSeniorConvertibleNotesDue214Member
London Interbank Offered Rate (LIBOR) [Member] | Floating Rate Notes Due September 10, 2015 [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt variable interest rate |  |  |  |  | 0.40%us-gaap_LongTermDebtPercentageBearingVariableInterestRate / us-gaap_LongtermDebtTypeAxis = mck_FloatingRateNotesDueSeptemberTenthTwoThousandFifteenMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember |

X
- Definition The amount offered to holders in cash of the outstanding principal amount + References No definition available. + Details
Name: | mck_ContingentPurchaseOfferSeries
Namespace Prefix: | mck_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of days notice before notes can be redeemed + References No definition available. + Details
Name: | mck_NumberOfDaysNoticeBeforeNotesCanBeRedeemed
Namespace Prefix: | mck_
Data Type: | xbrli:positiveIntegerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400 + Details
Name: | us-gaap_DebtInstrumentFaceAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_DebtInstrumentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentMaturityDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

X
- Definition Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20, 22 -Article 5 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
Name: | us-gaap_LongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04.(a)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690 + Details
Name: | us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04.(a)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690 + Details
Name: | us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04.(a)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690 + Details
Name: | us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04.(a)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690 + Details
Name: | us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04.(a)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690 + Details
Name: | us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04.(a)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690 + Details
Name: | us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LongTermDebtPercentageBearingVariableInterestRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585 + Details
Name: | us-gaap_ProceedsFromIssuanceOfLongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations. + References No definition available. + Details
Name: | us-gaap_RepaymentsOfDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_A4.00BondsDueOctober182016and4.50BondsDueApril262017Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_FivePointTwoFivePercentNotesDueMarchOneTwoThousandThirteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_FloatingRateNotesDueSeptemberTenthTwoThousandFifteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_FourPercentBondsDueOctoberEighteenTwoThousandSixteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_FourPointEightEightPercentNotesDueMarchFifteenthTwoThousandFortyFourMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_FourPointFivePercentBondsDueAprilTwentySixTwoThousandSeventeenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_OnePointFourZeroPercentNotesDueMarchFifteenthTwoThousandEighteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_OnePointTwoNinePercentNotesDueMarchTenthTwoThousandSeventeenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_PromissoryNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_SeniorConvertibleNotesDue2014Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_SeniorNotesDue2022AndSeniorConvertibleNotesDue214Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_SeniorNotesDue2022Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_SixPointFiveZeroPercentNotesDueFebruaryFifteenTwoThousandFourteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_TermLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_ThreePointEightZeroPercentNotesDueMarchFifteenthTwoThousandTwentyFourMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_TwoPointEightFivePercentNotesDueMarchFifteenTwoThousandTwentyThreeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_TwoPointSevenZeroPercentNotesDueDecemberFifteenTwoThousandTwentyTwoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_TwoPointTwoEightNotesDueMarchFifteenthTwoThousandNineteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=mck_ZeroPointNineFivePercentNotesDueDecemberFourTwoThousandFifteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |