XML 67 R57.htm IDEA: XBRL DOCUMENT v3.8.0.1

Stockholders' Equity - Schedule of Other Comprehensive Income (Loss), Net of Tax (Details) - USD ($)	3 Months Ended		6 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net actuarial losses attributable to redeemable noncontrolling interest	$ 0	$ 0	$ 1,000,000	$ 1,000,000
Other comprehensive income (loss) before reclassifications	258,000,000		578,000,000
Reclassified to income statement, net of income tax expense	1,000,000		2,000,000
Other Comprehensive Income (Loss), Net of Tax	259,000,000	(114,000,000)	580,000,000	(358,000,000)
Foreign currency translation adjustments arising during period, tax	0	11,000,000	0	(1,000,000)
Reclassified to income statement, tax	0	0	0	0
Unrealized gains on cash flow hedges arising during period, tax	0	0	0	0
Net actuarial loss and prior service cost arising during the period, tax	0	0	0	0
Amortization of actuarial loss and prior service costs, tax	0	1,000,000	0	2,000,000
Foreign currency translation adjustments and other, tax	0	0	0	0
Foreign Currency Translation Adjustments, Net of Tax
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	303,000,000	(109,000,000)	685,000,000	(384,000,000)
Reclassified to income statement, net of income tax expense	0	0	0	20,000,000
Other Comprehensive Income (Loss), Net of Tax	303,000,000	(109,000,000)	685,000,000	(364,000,000)
Unrealized Gains (Losses) on Net Investment Hedges, Net of Tax
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	(38,000,000)	0	(108,000,000)	0
Reclassified to income statement, net of income tax expense	0	0	0	0
Other Comprehensive Income (Loss), Net of Tax	(38,000,000)	0	(108,000,000)	0
Unrealized gains (losses) on net investment hedges arising during period, tax	25,000,000	0	69,000,000	0
Reclassified to income statement, tax	0	0	0	0
Unrealized Gains (Losses) on Cash Flow Hedges, Net of Tax
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	(3,000,000)		11,000,000
Reclassified to income statement, net of income tax expense	0		0
Other Comprehensive Income (Loss), Net of Tax	(3,000,000)	(6,000,000)	11,000,000	(6,000,000)
Accumulated Defined Benefit Plans Adjustment, Net Prior Service and Net Gain (Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	0	0	0	0
Accumulated Defined Benefit Plans Adjustment, Amortization of Actuarial Loss and Prior Service Cost
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	1,000,000	1,000,000	2,000,000	4,000,000
Accumulated Defined Benefit Plans, Foreign Currency Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	(4,000,000)	0	(10,000,000)	8,000,000
Accumulated Defined Benefit Plans Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Net of Tax	$ (3,000,000)	$ 1,000,000	$ (8,000,000)	$ 12,000,000

X

- Definition

Other Comprehensive Income (Loss) Defined Benefit Plans Net Unamortized Gain Loss Attributable to Redeemable Noncontrolling Interest Arising During Period Net Of Tax

+ References

No definition available.

+ Details

Name:	mck_OtherComprehensiveIncomeLossDefinedBenefitPlansNetUnamortizedGainLossAttributabletoRedeemableNoncontrollingInterestArisingDuringPeriodNetOfTax
Namespace Prefix:	mck_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Other Comprehensive Income Translation Impact On Pension Plans, Tax

+ References

No definition available.

+ Details

Name:	mck_OtherComprehensiveIncomeTranslationImpactOnPensionPlansTax
Namespace Prefix:	mck_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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

X

- Definition

Amount of tax expense (benefit), before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section 45
-Paragraph 20
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64808268&loc=d3e32211-110900

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e640-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669646-108580

+ Details

Name:	us-gaap_OtherComprehensiveIncomeForeignCurrencyTranslationGainLossArisingDuringPeriodTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Amount of tax (expense) benefit of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) related to pension and other postretirement benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e689-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e640-108580

+ Details

Name:	us-gaap_OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Amount after tax, before reclassification adjustments of other comprehensive income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=66004921&loc=d3e1436-108581

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669686-108580

+ Details

Name:	us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Amount of tax expense (benefit) allocated to other comprehensive income (loss) before reclassification adjustment from accumulated other comprehensive income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 20
-Section 45
-Paragraph 11
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65896914&loc=d3e39076-109324

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e640-108580

+ Details

Name:	us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Amount of tax expense (benefit), after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669646-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e640-108580

+ Details

Name:	us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for translation gain (loss) realized upon the sale or liquidation of an investment in a foreign entity and foreign currency hedges that are designated and qualified as hedging instruments for hedges of the foreign currency exposure of a net investment in a foreign operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section 45
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=64808268&loc=d3e32262-110900

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e640-108580

+ Details

Name:	us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationReclassificationAdjustmentFromAOCIRealizedUponSaleOrLiquidationTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Amount after tax and reclassification adjustments of other comprehensive income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669619-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669625-108580

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=66004921&loc=d3e1436-108581

+ Details

Name:	us-gaap_OtherComprehensiveIncomeLossNetOfTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Amount of tax (expense) benefit related to cost (credit) of benefit changes attributable to plan participants' prior service resulting from a plan amendment or plan initiation that has not been recognized in net periodic benefit cost (credit).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e640-108580

+ Details

Name:	us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansBenefitPlanImprovementTaxEffect
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Amount after tax of reclassification adjustments of other comprehensive income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669686-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=66004921&loc=d3e1436-108581

+ Details

Name:	us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 20
-Section 45
-Paragraph 11
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65896914&loc=d3e39076-109324

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e640-108580

+ Details

Name:	us-gaap_ReclassificationFromAociCurrentPeriodTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedForeignCurrencyAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedNetInvestmentGainLossIncludingPortionAttributableToNoncontrollingInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedNetGainLossFromCashFlowHedgesIncludingPortionAttributableToNoncontrollingInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_StatementEquityComponentsAxis=mck_AccumulatedDefinedBenefitPlansAdjustmentNetPriorServiceandNetGainLossIncludingPortionAttributabletoNoncontrollingInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_StatementEquityComponentsAxis=mck_AccumulatedDefinedBenefitPlansAdjustmentAmortizationofActuarialLossPriorServiceCostandTransitionObligationIncludingPortionAttributabletoNoncontrollingInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_StatementEquityComponentsAxis=mck_AccumulatedDefinedBenefitPlansForeignCurrencyAdjustmentIncludingPortionAttributabletoNoncontrollingInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedDefinedBenefitPlansAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: