McKesson (MCK) 10-K 5 May 16 2016 FY Annual report Financial data

Document and Entity Information

Document and Entity Information Document - USD ($) $ in Billions	12 Months Ended
	Mar. 31, 2016	Apr. 30, 2016	Sep. 30, 2015
Document And Entity Information [Abstract]
Entity Registrant Name	McKESSON CORPORATION
Entity Central Index Key	927,653
Entity Tax Identification Number	943,207,296
Document Type	10-K
Current Fiscal Year End Date	--03-31
Document Period End Date	Mar. 31, 2016
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2,016
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Amendment Flag	false
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 42.5
Entity Common Stock, Shares Outstanding		225,020,523

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Income Statement [Abstract]
Revenues	$ 190,884	$ 179,045	$ 137,392
Cost of Sales	(179,468)	(167,634)	(129,040)
Gross Profit	11,416	11,411	8,352
Operating Expenses
Selling, distribution and administrative expenses	(7,276)	(7,901)	(5,388)
Research and development	(392)	(392)	(457)
Restructuring charges	(203)	0	0
Claim and litigation charges	0	(150)	(68)
Total Operating Expenses	(7,871)	(8,443)	(5,913)
Operating Income	3,545	2,968	2,439
Other Income, Net	58	63	32
Interest Expense	(353)	(374)	(300)
Income from Continuing Operations Before Income Taxes	3,250	2,657	2,171
Income Tax Expense	(908)	(815)	(757)
Income from Continuing Operations	2,342	1,842	1,414
Loss from Discontinued Operations, Net of Tax	(32)	(299)	(156)
Net Income	2,310	1,543	1,258
Net (Income) Loss Attributable to Noncontrolling Interests	(52)	(67)	5
Net Income Attributable to McKesson Corporation	$ 2,258	$ 1,476	$ 1,263
Diluted
Continuing operations (in dollars per share)	$ 9.84	$ 7.54	$ 6.08
Discontinued operations (in dollars per share)	(0.14)	(1.27)	(0.67)
Total (in dollars per share)	9.70	6.27	5.41
Basic
Continuing operations (in dollars per share)	9.96	7.66	6.19
Discontinued operations (in dollars per share)	(0.14)	(1.29)	(0.68)
Total (in dollars per share)	$ 9.82	$ 6.37	$ 5.51
Weighted Average Common Shares
Diluted (in shares)	233	235	233
Basic (in shares)	230	232	229

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 2,310	$ 1,543	$ 1,258
Other Comprehensive Income (Loss), Net of Tax
Foreign currency translation adjustments arising during the period	113	(1,855)	53
Unrealized losses on cash flow hedges arising during the period	9	(10)	(6)
Retirement-related benefit plans	50	(124)	36
Other Comprehensive Income (Loss), Net of Tax	172	(1,989)	83
Comprehensive Income (Loss)	2,482	(446)	1,341
Comprehensive (Income) Loss Attributable to Noncontrolling Interests	(72)	212	(16)
Comprehensive Income (Loss) Attributable to McKesson Corporation	$ 2,410	$ (234)	$ 1,325

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Mar. 31, 2016	Mar. 31, 2015
Current Assets
Cash and cash equivalents	$ 4,048	$ 5,341
Receivables, net	17,980	15,914
Inventories, net	15,335	14,296
Prepaid expenses and other	1,074	1,119
Total Current Assets	38,437	36,670
Property, Plant and Equipment, Net	2,278	2,045
Goodwill	9,786	9,817
Intangible Assets, Net	3,021	3,441
Other Noncurrent Assets	3,041	1,897
Total Assets	56,563	53,870
Current Liabilities
Drafts and accounts payable	28,585	25,166
Short-term borrowings	7	135
Deferred revenue	919	1,078
Deferred tax liabilities	0	1,820
Current portion of long-term debt	1,612	1,529
Other accrued liabilities	3,948	3,769
Total Current Liabilities	35,071	33,497
Long-Term Debt	6,535	8,180
Long-Term Deferred tax liabilities	2,734	859
Other Noncurrent Liabilities	1,809	1,863
Commitments and Contingent Liabilities (Note 24)	0	0
Redeemable Noncontrolling Interests	1,406	1,386
McKesson Corporation Stockholders’ Equity
Preferred stock, $0.01 par value, 100 shares authorized, no shares issued or outstanding	0	0
Common stock, $0.01 par value, 800 shares authorized at March 31, 2016 and 2015, 271 and 384 shares issued at March 31, 2016 and 2015	3	4
Additional Paid-in Capital	5,845	6,968
Retained Earnings	8,360	12,705
Accumulated Other Comprehensive Loss	(1,561)	(1,713)
Other	(2)	(7)
Treasury Shares, at Cost, 46 and 152 at March 31, 2016 and 2015	(3,721)	(9,956)
Total McKesson Corporation Stockholders’ Equity	8,924	8,001
Noncontrolling Interests	84	84
Total Equity	9,008	8,085
Total Liabilities, Redeemable Noncontrolling Interests and Equity	$ 56,563	$ 53,870

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Mar. 31, 2016	Mar. 31, 2015
McKesson Corporation Stockholders’ Equity
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	100,000,000	100,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	800,000,000	800,000,000
Common stock, shares issued	271,000,000	384,000,000
Treasury stock, shares	46,000,000	152,000,000

CONSOLIDATED STATEMENTS OF STOC

CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Additional Paid-in Capital	Other Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury	Noncontrolling Interests
Beginning balance, common stock (in shares) at Mar. 31, 2013		376
Beginning balance at Mar. 31, 2013	$ 7,070	$ 4	$ 6,078	$ 14	$ 10,402	$ (65)	$ (9,363)	$ 0
Beginning balance, treasury common shares at Mar. 31, 2013							(149)
Issuance of shares under employee plans (in shares)		5					1
Issuance of shares under employee plans, tax portion of RSU issued	47		177				$ (130)
Share-based compensation	160		160
Tax benefit related to issuance of shares under employee plans	92		92
Acquisition of Celesio	1,500							1,500
Conversion of Celesio convertible bonds	313		33					280
Other comprehensive income	83					62		21
Net income (loss)	1,258				1,263			(5)
Repurchase of common stock	0		14				(14)
Cash dividends declared	(214)				(214)
Other	9		(2)	9	2
Ending balance common stock (in shares) at Mar. 31, 2014		381
Ending balance at Mar. 31, 2014	10,318	$ 4	6,552	23	11,453	(3)	$ (9,507)	1,796
Ending balance, treasury common shares at Mar. 31, 2014							(150)
Issuance of shares under employee plans (in shares)		3
Issuance of shares under employee plans, tax portion of RSU issued	43		152				$ (109)
Share-based compensation	165		165
Tax benefit related to issuance of shares under employee plans	105		105
Conversion of Celesio convertible bonds	0
Purchase of noncontrolling interests	(62)		(2)					(60)
Reclassification of noncontrolling interests to redeemable noncontrolling interests	(1,500)							(1,500)
Other comprehensive income	(1,884)					(1,710)		(174)
Net income (loss)	1,481				1,476			5
Repurchase of common stock (in shares)							(2)
Repurchase of common stock	(340)						$ (340)
Cash dividends declared	(226)				(226)
Other	(15)		(4)	(30)	2			17
Ending balance common stock (in shares) at Mar. 31, 2015		384
Ending balance at Mar. 31, 2015	$ 8,085	$ 4	6,968	(7)	12,705	(1,713)	$ (9,956)	84
Ending balance, treasury common shares at Mar. 31, 2015	(152)						(152)
Issuance of shares under employee plans (in shares)		3					1
Issuance of shares under employee plans, tax portion of RSU issued	$ 14		123				$ (109)
Share-based compensation	130		130
Tax benefit related to issuance of shares under employee plans	117		117
Conversion of Celesio convertible bonds	0
Other comprehensive income	152					152
Net income (loss)	2,266				2,258			8
Repurchase of common stock (in shares)							(9)
Repurchase of common stock	$ (1,504)						$ (1,504)
Retirement of common stock (in shares)	(115.5)	(116)					(116)
Retirement of common stock	$ 0	$ (1)	(1,493)		(6,354)		$ (7,848)
Cash dividends declared	(249)				(249)
Other	(3)			5				(8)
Ending balance common stock (in shares) at Mar. 31, 2016		271
Ending balance at Mar. 31, 2016	$ 9,008	$ 3	$ 5,845	$ (2)	$ 8,360	$ (1,561)	$ (3,721)	$ 84
Ending balance, treasury common shares at Mar. 31, 2016	(46)						(46)

CONSOLIDATED STATEMENTS OF STO7

CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (Parentheticals) - $ / shares	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Statement of Stockholders' Equity [Abstract]
Cash dividends declared per common share (in dollars per share)	$ 1.08	$ 0.96	$ 0.92

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Operating Activities
Net income	$ 2,310	$ 1,543	$ 1,258
Adjustments to reconcile to net cash provided by operating activities:
Depreciation	281	306	185
Amortization	604	711	550
Deferred taxes	64	171	17
Share-based compensation expense	123	174	160
Gain from sales of businesses	(103)	0	0
Impairment charges and impairment of equity investment	8	241	80
Charges associated with last-in-first-out inventory method	244	337	311
Other non-cash items	108	47	130
Changes in operating assets and liabilities, net of acquisitions:
Receivables	(1,957)	(2,821)	(868)
Inventories	(1,251)	(2,144)	(1,182)
Drafts and accounts payable	3,302	4,718	2,412
Deferred revenue	(120)	(141)	(81)
Taxes	(78)	(222)	218
Claim and litigation charges	0	150	68
Litigation settlement payments	0	0	(105)
Other	137	42	(17)
Net cash provided by operating activities	3,672	3,112	3,136
Investing Activities
Payments for property, plant and equipment	(488)	(376)	(278)
Capitalized software expenditures	(189)	(169)	(141)
Acquisitions, net of cash and cash equivalents acquired	(40)	(170)	(4,634)
Proceeds from sale of businesses and equity investment, net	210	15	97
Restricted cash for acquisitions	(939)	0	46
Other	(111)	23	(136)
Net cash used in investing activities	(1,557)	(677)	(5,046)
Financing Activities
Proceeds from short-term borrowings	1,561	3,100	6,080
Repayments of short-term borrowings	(1,688)	(3,152)	(6,132)
Proceeds from issuances of long-term debt	0	3	4,124
Repayments of long-term debt	(1,598)	(353)	(348)
Common stock transactions:
Issuances	123	152	177
Share repurchases, including shares surrendered for tax withholding	(1,612)	(450)	(130)
Dividends paid	(244)	(227)	(214)
Other	5	(41)	62
Net cash (used in) provided by financing activities	(3,453)	(968)	3,619
Effect of exchange rate changes on cash and cash equivalents	45	(319)	28
Net (decrease) increase in cash and cash equivalents	(1,293)	1,148	1,737
Cash and cash equivalents at beginning of year	5,341	4,193	2,456
Cash and cash equivalents at end of year	4,048	5,341	4,193
Cash paid for:
Interest	337	359	255
Income taxes, net of refunds	923	866	508
Non-cash item:
Fair value of debt assumed on acquisitions	0	0	(2,312)
Conversion of Celesio’s convertible bonds to equity	$ 0	$ 0	$ 313

Significant Accounting Policies

Significant Accounting Policies	12 Months Ended
	Mar. 31, 2016
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies Nature of Operations : McKesson Corporation (“McKesson,” the “Company,” the “Registrant” or “we” and other similar pronouns) delivers a comprehensive offering of pharmaceuticals and medical supplies and provides services to help our customers improve the efficiency and effectiveness of their healthcare operations. We manage our business through two operating segments, McKesson Distribution Solutions and McKesson Technology Solutions, as further described in Financial Note 27, “Segments of Business.” Basis of Presentation: The consolidated financial statements and accompanying notes are prepared in accordance with U. S. generally accepted accounting principles (“GAAP”). The consolidated financial statements of McKesson include the financial statements of all wholly-owned subsidiaries and majority-owned or controlled companies. For those consolidated subsidiaries where our ownership is less than 100% , the portion of the net income or loss allocable to the noncontrolling interests is reported as “Net Income Attributable to Noncontrolling Interests” on the consolidated statements of operations. All significant intercompany balances and transactions have been eliminated in consolidation. We consider ourselves to control an entity if we are the majority owner of and have voting control over such entity. We also assess control through means other than voting rights (“variable interest entities” or “VIEs”) and determine which business entity is the primary beneficiary of the VIE. We consolidate VIEs when it is determined that we are the primary beneficiary of the VIE. Investments in business entities in which we do not have control, but have the ability to exercise significant influence over operating and financial policies, are accounted for using the equity method and our proportionate share of income or loss is recorded in other income, net. Equity investments in non-publicly traded entities are primarily accounted for using the cost method. Intercompany transactions and balances have been eliminated. Fiscal Period: The Company’s fiscal year begins on April 1 and ends on March 31. Unless otherwise noted, all references to a particular year shall mean the Company’s fiscal year. Reclassifications : Certain prior year amounts have been reclassified to conform to the current year presentation. Use of Estimates : The preparation of financial statements in conformity with U.S. GAAP requires that we make estimates and assumptions that affect the reported amounts in the consolidated financial statements and accompanying notes. Actual amounts could differ from those estimated amounts. Cash and Cash Equivalents : All highly liquid debt and money market instruments purchased with original maturity of three months or less at the date of acquisition are included in cash and cash equivalents. Cash equivalents, which are available-for-sale, are carried at fair value. Cash equivalents are primarily invested in AAA rated prime and U.S. government money market funds denominated in U.S. dollars, AAA rated prime money market funds denominated in Euros, overnight repurchase agreements collateralized by U.S. government securities, Canadian government securities and/or securities that are guaranteed or sponsored by the U.S. government and an AAA rated prime money market fund denominated in British pound sterling. The remaining cash and cash equivalents are deposited with several financial institutions. Deposits may exceed the amounts insured by the Federal Deposit Insurance Corporation in the U.S. and similar deposit insurance programs in other jurisdictions. We mitigate the risk of our short-term investment portfolio by depositing funds with reputable financial institutions and monitoring risk profiles and investment strategies of money market funds. Restricted Cash : Cash that is subject to legal restrictions or is unavailable for general operating purposes is classified as restricted cash and is included within “Prepaid expenses and other” and “Other Noncurrent Assets” in the consolidated balance sheets. At March 31, 2016 , our restricted cash balance was $939 million , which represents cash paid into the escrow accounts for acquisitions that closed on April 1, 2016. There was no material restricted cash balance at March 31, 2015. Marketable Securities Available-for-Sale : We carry our marketable securities, which are available-for-sale, at fair value and they are included in prepaid expenses and other in the consolidated balance sheets. The unrealized gains and losses, net of the related tax effect, computed in marking these securities to market have been reported within stockholders’ equity. At March 31, 2016 and 2015 , marketable securities were not material. In determining whether an other-than-temporary decline in market value has occurred, we consider the duration that, and extent to which, the fair value of the investment is below its cost, the financial condition and future prospects of the issuer or underlying collateral of a security, and our intent and ability to retain the security in order to allow for an anticipated recovery in fair value. Other-than-temporary declines in fair value from amortized cost for available-for-sale equity securities that we intend to sell or would more likely than not be required to sell before the expected recovery of the amortized cost basis are charged to other income, net, in the period in which the loss occurs. Concentrations of Credit Risk and Receivables: Our trade receivables are subject to a concentration of credit risk with customers primarily in our Distribution Solutions segment. During 2016 , sales to our ten largest customers, including group purchasing organizations (“GPOs”) accounted for approximately 52.4% of our total consolidated revenues. Sales to our largest customer, CVS Health (“CVS”), accounted for approximately 20.3% of our total consolidated revenues. At March 31, 2016 , trade accounts receivable from our ten largest customers were approximately 32% of total trade accounts receivable. Accounts receivable from CVS were approximately 18% of total trade accounts receivable. As a result, our sales and credit concentration is significant. We also have agreements with GPOs, each of which functions as a purchasing agent on behalf of member hospitals, pharmacies and other healthcare providers, as well as with government entities and agencies. The accounts receivables balances are with individual members of the GPOs, and therefore no significant concentration of credit risk exists. A default in payment, a material reduction in purchases from these or any other large customers, or the loss of a large customer or customer groups could have a material adverse impact on our financial condition, results of operations and liquidity. In addition, trade receivables are subject to a concentration of credit risk with customers in the institutional, retail and healthcare provider sectors, which can be affected by a downturn in the economy and changes in reimbursement policies. This credit risk is mitigated by the size and diversity of the customer base as well as its geographic dispersion. We estimate the receivables for which we do not expect full collection based on historical collection rates and ongoing evaluations of the creditworthiness of our customers. An allowance is recorded in our consolidated financial statements for these amounts. Financing Receivables: We assess and monitor credit risk associated with financing receivables, namely lease and notes receivables, through regular review of our collection experience in determining our allowance for loan losses. On an ongoing basis, we also evaluate credit quality of our financing receivables utilizing aging of receivables and write-offs, as well as considering existing economic conditions, to determine if an allowance is necessary. Financing receivables are derecognized if legal title to them has been transferred and all related risks and rewards incidental to ownership have passed to the buyer. As of March 31, 2016 and 2015 , financing receivables and the related allowance were not material to our consolidated financial statements. Inventories: We report inventories at the lower of cost or market (“LCM”). Inventories for our Distribution Solutions segment consist of merchandise held for resale. For our Distribution Solutions segment, the majority of the cost of domestic inventories is determined using the last-in, first-out (“LIFO”) method. The majority of the cost of inventories held in foreign locations is based on weighted average purchase prices using the first-in, first-out method (“FIFO”). Technology Solutions segment inventories consist of computer hardware with cost generally determined by the standard cost method, which approximates average cost. Rebates, cash discounts, and other incentives received from vendors are recognized within cost of sales upon the sale of the related inventory. The LIFO method was used to value approximately 74% and 73% of our inventories at March 31, 2016 and 2015 . If we had used the FIFO method of inventory valuation, which approximates current replacement costs, inventories would have been approximately $1,012 million and $768 million higher than the amounts reported at March 31, 2016 and 2015 , respectively. These amounts are equivalent to our LIFO reserves. Our LIFO valuation amount includes both pharmaceutical and non-pharmaceutical products. In 2016 , 2015 and 2014 , we recognized LIFO related expenses of $244 million , $337 million and $311 million in cost of sales within our consolidated statements of operations. A LIFO expense is recognized when the net effect of price increases on pharmaceutical and non-pharmaceutical products held in inventory exceeds the impact of price declines, including the effect of branded pharmaceutical products that have lost market exclusivity. A LIFO credit is recognized when the net effect of price declines exceeds the impact of price increases on pharmaceutical and non-pharmaceutical products held in inventory. We believe that the average inventory costing method provides a reasonable estimation of the current cost of replacing inventory (i.e., “market”). As such, our LIFO inventory is valued at the lower of LIFO or market. Due to cumulative net price deflation from 2005 to 2013, we had a lower-of-cost or market (“LCM”) reserve of $60 million at March 31, 2013 which reduced pharmaceutical inventories at LIFO to market. During 2014, the LCM reserve of $60 million was released, resulting in an increase in gross profit. As of March 31, 2016 and 2015, inventories at LIFO did not exceed market. Shipping and Handling Costs: We include costs to pack and deliver inventory to our customers in selling, distribution and administrative expenses. Shipping and handling costs of $789 million , $819 million , $535 million were included in our selling, distribution and administrative expenses in 2016, 2015 and 2014. Property, Plant and Equipment: We state our property, plant and equipment (“PPE”) at cost and depreciate them under the straight-line method at rates designed to distribute the cost of PPE over estimated service lives ranging from one to thirty years. When certain events or changes in operating conditions occur, an impairment assessment may be performed on the recoverability of the carrying amounts. Goodwill: Goodwill is tested for impairment on an annual basis in the fourth quarter or more frequently if indicators for potential impairment exist. Impairment testing is conducted at the reporting unit level, which is generally defined as a component, one level below our Distribution Solutions and Technology Solutions operating segments, for which discrete financial information is available and segment management regularly reviews the operating results of that unit. The first step in goodwill testing requires us to compare the estimated fair value of a reporting unit to its carrying value. This step may be performed utilizing either a qualitative or quantitative assessment. If the carrying value of the reporting unit is lower than its estimated fair value, no further evaluation is necessary. If the carrying value of the reporting unit is higher than its estimated fair value, the second step must be performed to measure the amount of impairment loss. Under the second step, the implied fair value of goodwill is calculated in a hypothetical analysis by subtracting the fair value of all assets and liabilities of the reporting unit, including any unrecognized intangible assets, from the fair value of the reporting unit calculated in the first step of the impairment test. If the carrying value of goodwill for the reporting unit exceeds the implied fair value of goodwill, an impairment charge is recorded for that excess. To estimate the fair value of our reporting units, we use a combination of the market approach and the income approach. Under the market approach, we estimate fair value by comparing the business to similar businesses or guideline companies whose securities are actively traded in public markets. Under the income approach, we use a discounted cash flow model in which cash flows anticipated over several periods, plus a terminal value at the end of that time horizon, are discounted to their present value using an appropriate expected rate of return. The discount rate used for cash flows reflects capital market conditions and the specific risks associated with the business. In addition, we compare the aggregate of the reporting units’ fair value to the Company’s market capitalization as a further corroboration of the fair values. The testing requires a complex series of assumptions and judgment by management in projecting future operating results, selecting guideline companies for comparisons and assessing risks. The use of alternative assumptions and estimates could affect the fair values and change the impairment determinations. Intangible Assets: Currently all of our intangible assets are subject to amortization and are amortized based on the pattern of their economic consumption or on a straight-line basis over their estimated useful lives, ranging from one to thirty-eight years. We review intangible assets for impairment whenever events or changes in circumstances indicate that the carrying value of the assets may not be recoverable. Determination of recoverability is based on the lowest level of identifiable estimated future undiscounted cash flows resulting from use of the asset and its eventual disposition. Measurement of any impairment loss is based on the excess of the carrying value of the asset over its fair market value. Capitalized Software Held for Sale: Development costs for software held for sale, which primarily pertain to our Technology Solutions segment, are capitalized once a project has reached the point of technological feasibility. Completed projects are amortized after reaching the point of general availability using the straight-line method based on an estimated useful life of approximately three years. At each balance sheet date, or earlier if an indicator of an impairment exists, we evaluate the recoverability of unamortized capitalized software costs based on estimated future undiscounted revenues net of estimated related costs over the remaining amortization period. Capitalized Software Held for Internal Use: We capitalize costs of software held for internal use during the application development stage of a project and amortize those costs over their estimated useful lives ranging from one to ten years. As of March 31, 2016 and 2015 , capitalized software held for internal use was $435 million , net of accumulated amortization of $1,130 million and $1,112 million , and was included in other assets in the consolidated balance sheets. Insurance Programs: Under our insurance programs, we seek to obtain coverage for catastrophic exposures as well as those risks required to be insured by law or contract. It is our policy to retain a significant portion of certain losses primarily related to workers’ compensation and comprehensive general, product and vehicle liability. Provisions for losses expected under these programs are recorded based upon our estimate of the aggregate liability for claims incurred as well as for claims incurred but not yet reported. Such estimates utilize certain actuarial assumptions followed in the insurance industry. Revenue Recognition: Distribution Solutions Revenues for our Distribution Solutions segment are recognized when persuasive evidence of an arrangement exists, product is delivered and title passes to the customer or when services have been rendered and there are no further obligations to the customer, the price is fixed or determinable, and collection of the amounts are reasonably assured. Revenues for our Distribution Solutions segment include large volume sales of pharmaceuticals primarily to a limited number of large customers who warehouse their own products. We order bulk product from the manufacturer, receive and process the product primarily through our central distribution facility and deliver the bulk product (generally in the same form as received from the manufacturer) directly to our customers’ warehouses. We also record revenues for direct store deliveries of shipments from the manufacturer to our customers. We assume the primary liability to the manufacturer for these products. Revenues are recorded gross when we are the primary party obligated in the transaction, take title to and possession of the inventory, are subject to inventory risk, have latitude in establishing prices, assume the risk of loss for collection from customers as well as delivery or return of the product, are responsible for fulfillment and other customer service requirements, or the transactions have several but not all of these indicators. Revenues are recorded net of sales returns, allowances, rebates and other incentives. Our sales return policy generally allows customers to return products only if they can be resold for value or returned to suppliers for credit. Sales returns are accrued based on estimates at the time of sale to the customer. Sales returns from customers were approximately $3.1 billion in 2016 , $2.7 billion in 2015 and $1.9 billion in 2014 . Taxes collected from customers and remitted to governmental authorities are presented on a net basis; that is, they are excluded from revenues. Our Distribution Solutions segment also engages in multiple-element arrangements, which may contain a combination of various products and services. Revenue from a multiple-element arrangement is allocated to the separate elements based on their relative selling price and recognized in accordance with the revenue recognition criteria applicable to each element. Relative selling price is determined based on vendor-specific objective evidence (“VSOE”) of selling price, if available, third-party evidence (“TPE”), if VSOE of selling price is not available, or estimated selling price (“ESP”), if neither VSOE of selling price nor TPE is available. Technology Solutions Revenues for our Technology Solutions segment are generated primarily by licensing software and software systems (consisting of software, hardware and maintenance support), providing software as a service (“Saas”) or SaaS-based solutions and providing claims processing, outsourcing and professional services. Revenue for this segment is recognized as follows: Software systems are marketed under information systems agreements as well as service agreements. Perpetual software arrangements are recognized at the time of delivery or under the percentage-of-completion method if the arrangements require significant production, modification or customization of the software. Contracts accounted for under the percentage-of-completion method are generally measured based on the ratio of labor hours incurred to date to total estimated labor hours to be incurred. Changes in estimates to complete and revisions in overall profit estimates on these contracts are charged to earnings in the period in which they are determined. We accrue for contract losses if and when the current estimate of total contract costs exceeds total contract revenue. Revenue from time-based software license agreements is recognized ratably over the term of the agreement. Software implementation fees are recognized as the work is performed or under the percentage-of-completion method. Maintenance and support agreements are marketed under annual or multi-year agreements and are recognized ratably over the period covered by the agreements. Hardware revenues are generally recognized upon delivery. SaaS-based subscription, content and transaction processing fees are generally marketed under annual and multi-year agreements and are recognized ratably over the contracted terms beginning on the service start date for fixed fee arrangements and recognized as transactions are performed beginning on the service start date for per-transaction fee arrangements. Remote processing service fees are recognized monthly as the service is performed. Outsourcing service revenues are recognized as the service is performed. We also offer certain products on an application service provider basis, making our software functionality available on a remote hosting basis from our data centers. The data centers provide system and administrative support, as well as hosting services. Revenue on products sold on an application service provider basis is recognized on a monthly basis over the term of the contract beginning on the service start date of products hosted. This segment engages in multiple-element arrangements, which may contain any combination of software, hardware, implementation, SaaS-based offerings, consulting services or maintenance services. For multiple-element arrangements that do not include software, revenue is allocated to the separate elements based on their relative selling price and recognized in accordance with the revenue recognition criteria applicable to each element. Relative selling price is determined based on VSOE of selling price if available, TPE, if VSOE of selling price is not available, or ESP if neither VSOE of selling price nor TPE is available. For multiple-element arrangements accounted for in accordance with specific software accounting guidance when some elements are delivered prior to others in an arrangement and VSOE of fair value exists for the undelivered elements, revenue for the delivered elements is recognized upon delivery of such items. The segment establishes VSOE for hardware and implementation and consulting services based on the price charged when sold separately, and for maintenance services, based on renewal rates offered to customers. Revenue for the software element is recognized under the residual method only when fair value has been established for all of the undelivered elements in an arrangement. If fair value cannot be established for any undelivered element, all of the arrangement’s revenue is deferred until the delivery of the last element or until the fair value of the undelivered element is determinable. For multiple-element arrangements with both software elements and nonsoftware elements, arrangement consideration is allocated between the software elements as a whole and nonsoftware elements. The segment then further allocates consideration to the individual elements within the software group, and revenue is recognized for all elements under the applicable accounting guidance and our policies described above. Supplier Incentives: Fees for service and other incentives received from suppliers, relating to the purchase or distribution of inventory, are generally reported as a reduction to cost of sales. We consider these fees and other incentives to represent product discounts and as a result, the amounts are recognized within cost of sales upon the sale of the related inventory. Supplier Reserves: We establish reserves against amounts due from suppliers relating to various fees for services and price and rebate incentives, including deductions taken against payments otherwise due to them. These reserve estimates are established based on judgment after considering the status of current outstanding claims, historical experience with the suppliers, the specific incentive programs and any other pertinent information available. We evaluate the amounts due from suppliers on a continual basis and adjust the reserve estimates when appropriate based on changes in factual circumstances. All adjustments to supplier reserves are included in cost of sales. The ultimate outcome of any outstanding claims may be different than our estimate. As of March 31, 2016 and 2015 supplier reserves were $144 million and $167 million . All of the supplier reserves at March 31, 2016 and 2015 pertain to our Distribution Solutions segment. Income Taxes: We account for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements. Under this method, deferred tax assets and liabilities are determined based on the difference between the financial statements and the tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Tax benefits from uncertain tax positions are recognized when it is more likely than not that the position will be sustained upon examination, including resolutions of any related appeals or litigation processes, based on the technical merits. The amount recognized is measured as the largest amount of tax benefit that is greater than 50 percent likely of being realized upon effective settlement. Deferred taxes are not provided on undistributed earnings of our foreign operations that are considered to be permanently reinvested. Foreign Currency Translation: The reporting currency of the Company and its subsidiaries is the U.S. dollar. Our foreign subsidiaries generally consider their local currency to be their functional currency. Foreign currency-denominated assets and liabilities of these foreign subsidiaries are translated into U.S. dollars at year-end exchange rates and revenues and expenses are translated at average exchange rates during the corresponding period, and stockholders’ equity accounts are primarily translated at historical exchange rates. Foreign currency translation adjustments are included in other comprehensive income or loss in the statements of consolidated comprehensive income, and the cumulative effect is included in the stockholders’ equity section of the consolidated balance sheets. Realized gains and losses from currency exchange transactions are recorded in operating expenses in the consolidated statements of operations and were not material to our consolidated results of operations in 2016 , 2015 or 2014 . We release cumulative translation adjustment from stockholders’ equity into net income as a gain or loss only upon complete or substantially complete liquidation of a controlling interest in a subsidiary or a group of assets within a foreign entity. We also release all or a pro rata portion of the cumulative translation adjustment into net income upon the sale of an equity method investment that is a foreign entity. Derivative Financial Instruments: Derivative financial instruments are used principally in the management of foreign currency exchange and interest rate exposures and are recorded on the consolidated balance sheets at fair value. If a derivative is designated as a fair value hedge, the changes in the fair value of the derivative and of the hedged item attributable to the hedged risk are recognized as a charge or credit to earnings. If the derivative is designated as a cash flow hedge, the effective portions of changes in the fair value of the derivative are included in other comprehensive income or loss in the statements of consolidated comprehensive income, and the cumulative effect is included in the stockholders’ equity section of the consolidated balance sheets. The cumulative changes in fair value are reclassified to the consolidated statements of operations when the hedged item affects earnings. We periodically evaluate hedge effectiveness, and ineffective portions of changes in the fair value of cash flow hedges are recognized as a charge or credit to earnings. Derivative instruments not designated as hedges are marked-to-market at the end of each accounting period with the change included in earnings. Comprehensive Income: Comprehensive income consists of two components, net income and other comprehensive income. Other comprehensive income refers to revenue, expenses, and gains and losses that under GAAP are recorded as an element of stockholders’ equity but are excluded from net income. Our other comprehensive income primarily consists of foreign currency translation adjustments from those subsidiaries where the local currency is the functional currency, unrealized gains and losses on cash flow hedges, as well as unrealized gains and losses on retirement-related benefit plans. Noncontrolling Interests and Redeemable Noncontrolling Interests: Noncontrolling interests represent the portion of profit or loss, net assets and comprehensive income that is not allocable to McKesson Corporation. In 2016 and 2015, net income attributable to noncontrolling interests primarily represents guaranteed dividends and recurring compensation that McKesson is obligated to pay to the noncontrolling shareholders of Celesio AG (“Celesio”). Noncontrolling interests with redemption features, such as put rights, that are not solely within the Company’s control are considered redeemable noncontrolling interests. Redeemable noncontrolling interests are presented outside of Stockholders’ Equity on our consolidated balance sheet. Refer to Financial Note 10, “Noncontrolling Interests and Redeemable Noncontrolling Interests,” for more information. Share-Based Compensation: We account for all share-based compensation transactions using a fair-value based measurement method. The share-based compensation expense, for the portion of the awards that is ultimately expected to vest, is recognized on a straight-line basis over the requisite service period. The compensation expense recognized has been classified in the consolidated statements of operations or capitalized on the consolidated balance sheets in the same manner as cash compensation paid to our employees. Loss Contingencies: We are subject to various claims, including claims with customers and vendors, pending and potential legal actions for damages, investigations relating to governmental laws and regulations and other matters arising out of the normal conduct of our business. When a loss is considered probable and reasonably estimable, we record a liability in the amount of our best estimate for the ultimate loss. However, the likelihood of a loss with respect to a particular contingency is often difficult to predict and determining a meaningful estimate of the loss or a range of loss may not be practicable based on the information available and the potential effect of future events and decisions by third parties that will determine the ultimate resolution of the contingency. Moreover, it is not uncommon for such matters to be resolved over many years, during which time relevant developments and new information must be reevaluated at least quarterly to determine both the likelihood of potential loss and whether it is possible to reasonably estimate a range of possible loss. When a material loss is probable but a reasonable estimate cannot be made, disclosure of the proceeding is provided. Disclosure is also provided when it is reasonably possible that a loss will be incurred or when it is reasonably possible that the amount of a loss will exceed the recorded provision. We review all contingencies at least quarterly to determine whether the likelihood of loss has changed and to assess whether a reasonable estimate of the loss or range of the loss can be made. As discussed above, development of a meaningful estimate of loss or a range of potential loss is complex when the outcome is directly dependent on negotiations with or decisions by third parties, such as regulatory agencies, the court system and other interested parties. Such factors bear directly on whether it is possible to reasonably estimate a range of potential loss and boundaries of high and low estimate. Business Combinations: We account for acquired businesses using the acquisition method of acc

Business Combinations

Business Combinations	12 Months Ended
	Mar. 31, 2016
Business Combinations [Abstract]
Business Combinations	Business Combinations Acquisition of Celesio AG On February 6, 2014, we completed the acquisition of 77.6% of the then outstanding common shares of Celesio and certain convertible bonds of Celesio for cash consideration of $4.5 billion , net of cash acquired (the “Acquisition”). Upon the acquisition, our ownership of Celesio’s fully diluted common shares was 75.6% and, as required, we consolidated Celesio’s debt with a fair value of $2.3 billion as a liability on our consolidated balance sheet. The Acquisition was initially funded by utilizing a senior bridge loan, our existing accounts receivable sales facility and cash on hand. Celesio is an international wholesale and retail company and a provider of logistics and services to the pharmaceutical and healthcare sectors. Celesio’s headquarters is in Stuttgart, Germany and it operates in 14 countries around the world. The acquisition of Celesio expanded our global geographic area. Financial results for continuing operations of Celesio are included within our International pharmaceutical distribution and services business, which is part of our Distribution Solutions segment, since the date of Acquisition. From February 7, 2014 through March 31, 2014, substantially all of the convertible bonds issued by Celesio (held by both third parties and us) were converted into an additional 20.9 million common shares of Celesio and approximately $30 million in cash. At March 31, 2014, we owned approximately 75.4% of Celesio’s outstanding and fully diluted common shares. Included in the purchase price allocation were acquired identifiable intangibles of $2.3 billion , the fair value of which was primarily determined by applying the income approach using unobservable inputs for projected cash flows and discount rates. These inputs are considered Level 3 under the fair value measurements and disclosure guidance. The fair value of the debt acquired was determined by quoted market prices in a less active market and other observable inputs from available market information, which are considered to be Level 2 inputs under the fair value measurements and disclosure guidance. The fair value of the noncontrolling interests for the Celesio common shares that were not acquired by McKesson was $1,505 million and was determined by a quoted market price that is considered to be a Level 1 input under the fair value measurements and disclosure guidance. The excess of the purchase price and the noncontrolling interests over the fair value of the acquired net assets of $4.2 billion has been allocated to goodwill, which primarily reflects the expected future benefits to be realized upon integrating the business. Most of the goodwill is not expected to be deductible for tax purposes. Refer to Financial Note 10, “Noncontrolling Interests and Redeemable Noncontrolling Interests” for information on the domination and profit and loss transfer agreement entered into between McKesson and Celesio during fiscal 2015. Other Acquisitions In July 2015, we entered into an agreement to purchase the pharmacy business of J Sainsbury Plc (“Sainsbury”) based in the United Kingdom (“U.K.”). Under the terms of the agreement, on February 29, 2016, we made an advance cash payment of $174 million representing the full purchase consideration, which is included in “Other Noncurrent Assets” within our consolidated balance sheet at March 31, 2016. The advance payment bears interest at an annual rate of 3.3% , compounded daily, from February 29, 2016 until the closing of the transaction. The interest will be paid to us in full on the closing date. The U.K. business is currently being reviewed by the U.K. Competition and Markets Authority (the “U.K. CMA”). We anticipate obtaining U.K. CMA clearance during the first quarter of 2017. Once completed, this acquisition will further enhance our retail pharmacy service capabilities in the U.K. Upon closing, the acquired Sainsbury business will be included in our International pharmaceutical distribution and services business within our Distribution Solutions segment. In September 2015, we entered into an agreement to purchase the pharmaceutical distribution business of UDG Healthcare Plc (“UDG”) based in Ireland and the U.K. During the fourth quarter of 2016, we paid the net purchase consideration of $412 million into an escrow account, which is included in “Other Noncurrent Assets” within our consolidated balance sheet at March 31, 2016. The acquisition was completed on April 1, 2016. The acquired UDG business primarily provides pharmaceutical and other healthcare products to retail and hospital pharmacies. The acquisition of UDG will expand our offerings and strengthen our market position in Ireland and the U.K. The U.K. business is currently being reviewed by the U.K. CMA and as a result, we have limited control over this portion of the acquired business. We anticipate obtaining U.K. CMA clearance during the second half of 2017. Upon closing, financial results for this acquisition will be included in our International pharmaceutical distribution and services business within our Distribution Solutions segment. On April 1, 2016, we acquired Vantage Oncology Holdings LLC (“Vantage”), which is headquartered in Manhattan Beach, California. Vantage provides comprehensive oncology management services, including radiation oncology, medical oncology, and other integrated cancer care services, through over 51 cancer treatment facilities in 13 states. The net purchase consideration of $527 million was paid into an escrow account prior to year end, and is included in “Other Noncurrent Assets” within our consolidated balance sheet at March 31, 2016. Also on April 1, 2016, we acquired Biologics, Inc. (“Biologics”) for gross purchase consideration of $700 million , which was funded from cash on hand. Biologics is the largest independent oncology-focused specialty pharmacy in the U.S., which is headquartered in Cary, North Carolina. The financial results of Vantage and Biologics will be included within our Distribution Solutions segment from the date of acquisition. These acquisitions will collectively enhance our specialty pharmaceutical distribution scale and oncology-focused pharmacy offerings, solutions for manufacturers and payers, and expand the scope of our community-based oncology and practice management services. In March 2016, we entered into an agreement to purchase Rexall Health from Katz Group for $3 billion Canadian dollars (or, approximately $2.3 billion U.S. dollars using the currency exchange ratio of 0.77 Canadian dollar to 1 U.S. dollar as of March 31, 2016). Rexall Health, which operates approximately 470 retail pharmacies in Canada, particularly in Ontario and Western Canada, will enhance our Canadian pharmaceutical supply chain. The acquisition is subject to regulatory approval and expected to close during the second half of calendar year 2016. Upon closing, the acquired business will be included within our Distribution Solutions segment. During the last three years, we also completed a number of other acquisitions within our Distribution Solutions segment. Financial results for our business acquisitions have been included in our consolidated financial statements since their respective acquisition dates. Purchase prices for our business acquisitions have been allocated based on estimated fair values at the date of acquisition. Goodwill recognized for our business acquisitions is generally not expected to be deductible for tax purposes. However, if we acquire the assets of a company, the goodwill may be deductible for tax purposes.

Restructuring

Restructuring	12 Months Ended
	Mar. 31, 2016
Restructuring and Related Activities [Abstract]
Restructuring	Restructuring On March 14, 2016, we committed to a restructuring plan to lower our operating costs (the “Cost Alignment Plan”). The Cost Alignment Plan primarily consists of a reduction in workforce, and business process initiatives that will be substantially implemented prior to the end of 2019. Business process initiatives primarily include plans to reduce operating costs of our distribution and pharmacy operations, administrative support functions, and technology platforms, as well as the disposal and abandonment of certain non-core businesses. As a result of the Cost Alignment Plan, we expect to record total pre-tax charges of approximately $270 million to $290 million , of which $229 million of pre-tax charges were recorded during the fourth quarter of 2016. Estimated remaining charges primarily consist of exit-related costs and accelerated depreciation and amortization, which are largely attributed to our Distribution Solutions segment. Restructuring charges for our Cost Alignment Plan during the fourth quarter of 2016 consisted of the following: (In millions) Distribution Solutions Technology Solutions Corporate Total Severance and employee-related costs, net (1) $ 147 $ 44 $ 16 $ 207 Exit-related costs 3 1 1 5 Asset impairments and accelerated depreciation and amortization (2) 11 6 — 17 Total $ 161 $ 51 $ 17 $ 229 Cost of Sales $ 5 $ 21 $ — $ 26 Operating Expenses 156 30 17 203 Total $ 161 $ 51 $ 17 $ 229 (1) Severance and employee-related costs, net, include charges of $117 million and $90 million , for a total of $207 million , for a reduction in workforce and business process initiatives. (2) Asset impairments and accelerated depreciation and amortization charges primarily include impairments for capitalized software projects and software licenses due to abandonments. The following table summarizes the activity related to the restructuring liabilities associated with the Cost Alignment Plan for the quarter and year ended March 31, 2016: Quarter and Year Ended March 31, 2016 (In millions) Balance March 31, 2015 Net restructuring charges recognized Non-cash charges Cash Payments Other Balance March 31, 2016 (1) 2016 Cost Alignment Plan Distribution Solutions $ — $ 161 $ (4 ) $ (1 ) $ — $ 156 Technology Solutions — 51 (3 ) — (3 ) 45 Corporate — 17 5 — (1 ) 21 Total 2016 Cost Alignment Plan $ — $ 229 $ (2 ) $ (1 ) $ (4 ) $ 222 (1) The reserve balances as of March 31, 2016 include $172 million recorded in other accrued liabilities and $50 million recorded in other noncurrent liabilities in our consolidated balance sheet.

Asset Impairments and Product A

Asset Impairments and Product Alignment Charges	12 Months Ended
	Mar. 31, 2016
Asset Impairment Charges [Abstract]
Asset Impairments and Product Alignment Charges	Asset Impairments and Product Alignment Charges In 2014, we recorded pre-tax charges totaling $57 million in our Technology Solutions segment. These charges primarily consist of $35 million of product alignment charges, $15 million of integration-related expenses and $7 million of reduction-in-workforce severance charges. Included in the total charge was $35 million for severance for employees primarily in our research and development, customer services and sales functions, and $15 million for asset impairments which primarily represents the write-off of deferred costs related to a product that will no longer be developed. Charges were recorded in our consolidated statement of operations as follows: $34 million in cost of sales and $23 million in operating expenses.

Divestiture of Businesses

Divestiture of Businesses	12 Months Ended
	Mar. 31, 2016
Discontinued Operation, Income (Loss) from Discontinued Operation Disclosures [Abstract]
Divestiture of Businesses	During the second quarter of 2016, we sold our ZEE Medical business within our Distribution Solutions segment for total proceeds of $134 million and recorded a pre-tax gain of $52 million ( $29 million after-tax) from this sale. During the first quarter of 2016, we also sold our nurse triage business within our Technology Solutions segment for net sale proceeds of $84 million and recorded a pre-tax gain of $51 million ( $38 million after-tax) from the sale. These divestitures did not meet the criteria to qualify as discontinued operations under the amended accounting guidance, which became effective for us in the first quarter of 2016. Accordingly, pre-tax gains from both divestitures were recorded in operating expenses within continuing operations of our consolidated statements of operations. Pre and after-tax income of these businesses were not material for the year ended March 31, 2016. Discontinued Operations Brazil Distribution Business During the fourth quarter of 2015, we committed to a plan to sell our Brazilian pharmaceutical distribution business, which we acquired through our February 2014 acquisition of Celesio, from our Distribution Solutions segment. Accordingly, the results of operations and cash flows of this business are classified as discontinued operations for all periods presented in our consolidated financial statements. During the fourth quarter of 2015, we recorded $241 million of non-cash pre-tax ( $235 million after-tax) impairment charges to reduce the carrying value of this Brazilian distribution business to its estimated fair value less costs to sell. The impairment charge reduced the carrying value of property, plant and equipment, other long-lived assets and goodwill by $31 million . The remaining difference between the business’ fair value and carrying value of $210 million was recorded as a liability and was included in other accrued liabilities in our consolidated balance sheet at March 31, 2015. Cumulative foreign currency translation losses of $17 million were included in the assessment of this business’ carrying value for purposes of calculating the impairment charge. Cumulative foreign currency translation losses, net of tax, were included in Accumulated Other Comprehensive Income on our consolidated balance sheet at March 31, 2015. On January 31, 2016, we entered into an agreement to sell our Brazilian pharmaceutical distribution business to a third party. The sale is expected to be completed during the first half of 2017, subject to regulatory approval and customary closing conditions. We expect to recognize an after-tax charge of approximately $80 million to $100 million upon the disposition of the business within discontinued operations as a result of settlement of certain indemnification matters. Technology Solutions Businesses In 2014, we committed to a plan to sell our International Technology and our Hospital Automation businesses from our Technology Solutions segment. As required, in 2014, we classified the results of operations and cash flows of these businesses as discontinued operations for all applicable periods presented in our consolidated financial statements. Depreciation and amortization expense was not recognized from the date these businesses were classified as held for sale. During the third quarter of 2014, we completed the sale of our Hospital Automation business and recorded a pre-tax and after-tax loss of $5 million and $7 million . During the third quarter of 2014, we recorded an $80 million non-cash pre-tax and after-tax impairment charge to reduce the carrying value of our International Technology business to its estimated fair value less costs to sell. The impairment charge was primarily attributed to goodwill and other long-lived assets and as a result, there was no tax benefit associated with this charge. During the first quarter of 2015, we decided to retain the workforce business within our International Technology business. This business consists of workforce management solutions for the National Health Service in the United Kingdom. We reclassified the workforce business, which had been designated as a discontinued operation since the first quarter of 2014, to continuing operations in the first quarter of 2015. As a result, during the first quarter of 2015, we recorded non-cash pre-tax charges of $34 million ( $27 million after-tax) primarily associated with depreciation and amortization expense for 2014 when the business was classified as held for sale. The non-cash charge was recorded in our consolidated statement of operations primarily in cost of sales. During the second quarter of 2015, we completed the sale of a software business within our International Technology business and recorded a pre-tax and after-tax loss of $6 million . A summary of results of discontinued operations is as follows: Years Ended March 31, (In millions) 2016 2015 2014 Revenues $ 1,603 $ 2,196 $ 637 Loss from discontinued operations $ (24 ) $ (321 ) $ (177 ) Loss on sale — (6 ) (5 ) Loss from discontinued operations before income tax (24 ) (327 ) (182 ) Income tax (expense) benefit (8 ) 28 26 Loss from discontinued operations, net of tax $ (32 ) $ (299 ) $ (156 ) A summary of carrying amounts of major classes of assets and liabilities included as part of discontinued operations is as follow: March 31, (In millions) 2016 2015 Receivables, net $ 289 $ 314 Inventories, net 266 254 Other assets 80 92 Total assets of discontinued operations (1) 635 660 Drafts and account payable 264 209 Short-term borrowings 142 126 Other liabilities 254 328 Total liabilities of discontinued operations (1) $ 660 $ 663 (1) Assets and liabilities of discontinued operations are included under the captions “Prepaid expenses and other” and “Other accrued liabilities” within our consolidated balance sheets.

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Mar. 31, 2016
Share-based Compensation [Abstract]
Share-Based Compensation	Share-Based Compensation We provide share-based compensation to our employees, officers and non-employee directors, including stock options, an employee stock purchase plan, restricted stock units (“RSUs”), performance-based restricted stock units (“PeRSUs”) and total shareholder return units (“TSRUs”) (collectively, “share-based awards”). Most of our share-based awards are granted in the first quarter of each fiscal year. Compensation expense for the share-based awards is recognized for the portion of awards ultimately expected to vest. We estimate the number of share-based awards that will ultimately vest primarily based on historical experience. The estimated forfeiture rate established upon grant is re-assessed throughout the requisite service period and is adjusted when actual forfeitures occur. The actual forfeitures in future reporting periods could be higher or lower than current estimates. The compensation expense recognized has been classified in the consolidated statements of operations or capitalized in the consolidated balance sheets in the same manner as cash compensation paid to our employees. There was no material share-based compensation expense capitalized as part of the cost of an asset in 2016 , 2015 and 2014 . Impact on Net Income The components of share-based compensation expense and related tax benefits are as follows: Years Ended March 31, (In millions) 2016 2015 2014 Restricted stock unit awards (1) $ 88 $ 137 $ 126 Stock options 22 24 22 Employee stock purchase plan 13 13 12 Share-based compensation expense (2) 123 174 160 Tax benefit for share-based compensation expense (3) (41 ) (61 ) (55 ) Share-based compensation expense, net of tax $ 82 $ 113 $ 105 (1) Includes compensation expense recognized for RSUs, PeRSUs and TSRUs. Our TSRUs were awarded beginning in 2015. (2) 2016 includes non-cash credits of $14 million representing the reversal of previously recognized share-based compensation, which was recorded due to employee terminations associated with the March 2016 restructuring plan. (3) Income tax benefit is computed using the tax rates of applicable tax jurisdictions. Additionally, a portion of pre-tax compensation expense is not tax-deductible. Stock Plans In July 2013, our stockholders approved the 2013 Stock Plan to replace the 2005 Stock Plan. These stock plans provide our employees, officers and non-employee directors the opportunity to receive equity-based, long-term incentives in the form of stock options, restricted stock, RSUs, PeRSUs, TSRUs and other share-based awards. The 2013 Stock Plan reserves 30 million shares plus the remaining number of shares reserved but unused under the 2005 Stock Plan. As of March 31, 2016 , 29 million shares remain available for future grant under the 2013 Stock Plan. Stock Options Stock options are granted with an exercise price at no less than the fair market value and those options granted under the stock plans generally have a contractual term of seven years and follow a four -year vesting schedule. Compensation expense for stock options is recognized on a straight-line basis over the requisite service period and is based on the grant-date fair value for the portion of the awards that is ultimately expected to vest. We use the Black-Scholes options-pricing model to estimate the fair value of our stock options. Once the fair value of an employee stock option is determined, current accounting practices do not permit it to be changed, even if the estimates used are different from actual. The options-pricing model requires the use of various estimates and assumptions as follows: • Expected stock price volatility is based on a combination of historical volatility of our common stock and implied market volatility. We believe that this market-based input provides a reasonable estimate of our future stock price movements and is consistent with employee stock option valuation considerations. • Expected dividend yield is based on historical experience and investors’ current expectations. • The risk-free interest rate for periods within the expected life of the option is based on the constant maturity U.S. Treasury rate in effect at the time of grant. • Expected life of the options is based primarily on historical employee stock option exercises and other behavior data and reflects the impact of changes in contractual life of current option grants compared to our historical grants. Weighted-average assumptions used to estimate the fair value of employee stock options were as follows: Years Ended March 31, 2016 2015 2014 Expected stock price volatility 21% 22% 22% Expected dividend yield 0.4% 0.6% 0.7% Risk-free interest rate 1.4% 1.3% 0.7% Expected life (in years) 4 4 4 The following is a summary of stock options outstanding at March 31, 2016 : Options Outstanding Options Exercisable Range of Exercise Prices Number of Options Outstanding at Year End (In millions) Weighted- Average Remaining Contractual Life (Years) Weighted- Average Exercise Price Number of Options Exercisable at Year End (In millions) Weighted- Average Exercise Price $ 40.46 – $ 140.19 3 2 $ 83.62 2 $ 78.01 140.20 – 239.93 1 6 206.58 — 180.24 4 2 The following table summarizes stock option activity during 2016 : (In millions, except per share data) Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (Years) Aggregate Intrinsic Value (2) Outstanding, March 31, 2015 5 $ 95.01 4 $ 539 Granted 1 236.77 Cancelled (1) 149.19 Exercised (1) 63.75 Outstanding, March 31, 2016 4 $ 118.95 3 $ 201 Vested and expected to vest (1) 3 $ 118.21 3 $ 200 Vested and exercisable, March 31, 2016 2 85.15 2 173 (1) The number of options expected to vest takes into account an estimate of expected forfeitures. (2) The intrinsic value is calculated as the difference between the period-end market price of the Company’s common stock and the exercise price of “in-the-money” options. The following table provides data related to stock option activity: Years Ended March 31, (In millions, except per share data) 2016 2015 2014 Weighted-average grant date fair value per stock option $ 44.04 $ 35.49 $ 21.45 Aggregate intrinsic value on exercise $ 107 $ 153 $ 144 Cash received upon exercise $ 47 $ 76 $ 111 Tax benefits realized related to exercise $ 42 $ 60 $ 55 Total fair value of stock options vested $ 18 $ 20 $ 24 Total compensation cost, net of estimated forfeitures, related to unvested stock options not yet recognized, pre-tax $ 20 $ 22 $ 29 Weighted-average period in years over which stock option compensation cost is expected to be recognized 2 2 1 Restricted Stock Unit Awards RSUs, which entitle the holder to receive at the end of a vesting term a specified number of shares of the Company’s common stock, are accounted for at fair value at the date of grant. Total compensation expense for RSUs under our stock plans is determined by the product of the number of shares that are expected to vest and the grant date market price of the Company’s common stock. The Compensation Committee determines the vesting terms at the time of grant. These awards generally vest in three to four years. We recognize expense for RSUs on a straight-line basis over the requisite service period. Non-employee directors receive an annual grant of RSUs, which vest immediately and are expensed upon grant. The director may elect to receive the underlying shares immediately or defer receipt of the shares if they meet director stock ownership guidelines. The shares will be automatically deferred for those directors who do not meet the director stock ownership guidelines. At March 31, 2016 , approximately 146 thousand RSUs for our directors are vested. PeRSUs are RSUs for which the number of RSUs awarded is conditional upon the attainment of one or more performance objectives over a specified period. Each year, the Compensation Committee approves the target number of PeRSUs representing the base number of awards that could be granted if performance goals are attained. PeRSUs are accounted for as variable awards until the performance goals are reached at which time the grant date is established. Total compensation expense for PeRSUs is determined by the product of the number of shares eligible to be awarded and expected to vest, and the market price of the Company’s common stock, commencing at the inception of the requisite service period. During the performance period, the compensation expense for PeRSUs is re-computed using the market price and the performance modifier at the end of a reporting period. At the end of the performance period, if the goals are attained, the awards are granted and classified as RSUs and accounted for on that basis. We recognize compensation expense for these awards on a straight-line basis over the requisite aggregate service period of generally four years. TSRUs replaced PeRSUs for our executive officers beginning in 2015. The number of vested TSRUs is assessed at the end of a three -year performance period and is conditioned upon attainment of a total shareholder return metric relative to a peer group of companies. We use the Monte Carlo simulation model to measure the fair value of TSRUs. TSRUs have a requisite service period of approximately three years. Expense is attributed to the requisite service period on a straight-line basis based on the fair value of the TSRUs. For TSRUs that are designated as equity awards, the fair value is measured at the grant date. For TSRUs that are eligible for cash settlement and designated as liability awards, we measure the fair value at the end of each reporting period and also adjust a corresponding liability on our balance sheet for changes in fair value. The weighted-average assumptions used to estimate the fair value of TSRUs are as follows: Years Ended March 31, 2016 2015 Expected stock price volatility 18% 21% Expected dividend yield 0.4% 0.5% Risk-free interest rate 0.9% 0.7% Expected life (in years) 3 3 The following table summarizes restricted stock unit award activity during 2016 : (In millions, except per share data) Shares Weighted- Average Grant Date Fair Value Per Share Nonvested, March 31, 2015 4 $ 129.57 Granted 1 240.35 Cancelled (1) 159.17 Vested (1) 89.44 Nonvested, March 31, 2016 3 $ 176.59 The following table provides data related to restricted stock unit award activity: Years Ended March 31, (In millions) 2016 2015 2014 Total fair value of shares vested $ 104 $ 126 $ 184 Total compensation cost, net of estimated forfeitures, related to nonvested restricted stock unit awards not yet recognized, pre-tax $ 144 $ 206 $ 236 Weighted-average period in years over which restricted stock unit award cost is expected to be recognized 2 2 2 Employee Stock Purchase Plan (“ESPP”) The Company has an ESPP under which 21 million shares have been authorized for issuance. The ESPP allows eligible employees to purchase shares of our common stock through payroll deductions. The deductions occur over three -month purchase periods and the shares are then purchased at 85% of the market price at the end of each purchase period. Employees are allowed to terminate their participation in the ESPP at any time during the purchase period prior to the purchase of the shares. The 15% discount provided to employees on these shares is included in compensation expense. The shares related to funds outstanding at the end of a quarter are included in the calculation of diluted weighted average shares outstanding. These amounts have not been significant. Shares issued under the ESPP were not material in 2016 , 2015 , and 2014. At March 31, 2016 , 4 million shares remain available for issuance.

Other Income, Net

Other Income, Net	12 Months Ended
	Mar. 31, 2016
Other Nonoperating Income (Expense) [Abstract]
Other Income, Net	Other Income, Net Years Ended March 31, (In millions) 2016 2015 2014 Interest income $ 18 $ 20 $ 16 Equity in earnings, net (1) 15 12 — Other, net (1) 25 31 16 Total $ 58 $ 63 $ 32 (1) Primarily recorded within our Distribution Solutions segment.

Income Taxes

Income Taxes	12 Months Ended
	Mar. 31, 2016
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Years Ended March 31, (In millions) 2016 2015 2014 Income from continuing operations before income taxes U.S. $ 2,319 $ 1,893 $ 1,554 Foreign 931 764 617 Total income from continuing operations before income taxes $ 3,250 $ 2,657 $ 2,171 Income tax expense related to continuing operations consists of the following: Years Ended March 31, (In millions) 2016 2015 2014 Current Federal $ 658 $ 453 $ 484 State 96 90 64 Foreign 90 101 193 Total current 844 644 741 Deferred Federal 95 195 24 State 42 53 10 Foreign (73 ) (77 ) (18 ) Total deferred 64 171 16 Income tax expense $ 908 $ 815 $ 757 During 2016, 2015 and 2014, income tax expense related to continuing operations was $908 million , $815 million and $757 million , which included net discrete tax benefits of $42 million and $33 million in 2016 and 2015 and net discrete tax expenses of $94 million in 2014. Discrete tax benefits in 2016 included a $19 million benefit related to enacted tax law changes in foreign jurisdictions and a $25 million benefit due to the reversal of a tax reserve related to the treatment of share-based compensation expense in an intercompany cost-sharing agreement. Discrete tax benefit in 2015 included a $55 million benefit related to an agreement reached with the Internal Revenue Service (“IRS”) to settle all outstanding issues relating to years 2003 through 2006. Discrete tax expense for 2014 primarily related to a $122 million charge regarding an unfavorable decision from the Tax Court of Canada with respect to transfer pricing issues. Our reported income tax rates were 27.9% , 30.7% , and 34.9% in 2016, 2015 and 2014. The fluctuations in our reported income tax rates are primarily due to changes within our business mix, including varying proportions of income attributable to foreign countries that have lower income tax rates and discrete items. The reconciliation between our effective tax rate on income from continuing operations and statutory tax rate is as follows: Years Ended March 31, (In millions) 2016 2015 2014 Income tax expense at federal statutory rate $ 1,137 $ 930 $ 760 State income taxes net of federal tax benefit 92 81 57 Foreign income taxed at various rates (295 ) (247 ) (177 ) Canadian litigation (8 ) — 122 Controlled substance distribution reserve — 58 — Unrecognized tax benefits and settlements (6 ) 10 (6 ) Tax credits (18 ) (10 ) (6 ) Other, net 6 (7 ) 7 Income tax expense $ 908 $ 815 $ 757 At March 31, 2016 , undistributed earnings of our foreign operations totaling $5,831 million were considered to be permanently reinvested. No deferred tax liability has been recognized on the basis difference created by such earnings since it is our intention to utilize those earnings in the foreign operations as well as to fund certain research and development activities for an indefinite period of time. The determination of the amount of deferred taxes on these earnings is not practicable because the computation would depend on a number of factors that cannot be known until a decision to repatriate the earnings is made. Deferred tax balances consisted of the following: March 31, (In millions) 2016 2015 Assets Receivable allowances $ 110 $ 83 Deferred revenue 77 72 Compensation and benefit related accruals 710 681 Net operating loss and credit carryforwards 367 316 Other 275 266 Subtotal 1,539 1,418 Less: valuation allowance (267 ) (229 ) Total assets 1,272 1,189 Liabilities Inventory valuation and other assets (2,619 ) (2,333 ) Fixed assets and systems development costs (326 ) (324 ) Intangibles (981 ) (1,073 ) Other (21 ) (61 ) Total liabilities (3,947 ) (3,791 ) Net deferred tax liability $ (2,675 ) $ (2,602 ) Current net deferred tax asset (1) $ — $ 27 Current net deferred tax liability (1) — (1,820 ) Long-term deferred tax asset 59 50 Long-term deferred tax liability (2,734 ) (859 ) Net deferred tax liability $ (2,675 ) $ (2,602 ) (1) Upon the adoption of the amended accounting guidance, we reclassified current net deferred tax liabilities and current net deferred tax assets as noncurrent on our consolidated balance sheet as of March 31, 2016. Our March 31, 2015 balances were not retrospectively reclassified. We assess the available positive and negative evidence to determine whether deferred tax assets are more likely than not to be realized. As a result of this assessment, valuation allowances have been recorded on certain deferred tax assets in various tax jurisdictions. The valuation allowance was approximately $267 million and $229 million in 2016 and 2015. The increase of $38 million in valuation allowances in the current year relate primarily to net operating losses incurred in certain tax jurisdictions for which no tax benefit was recognized. We have federal, state and foreign net operating loss carryforwards of $35 million , $1,790 million and $889 million . Federal and state net operating losses will expire at various dates from 2017 through 2036. Substantially all of our foreign net operating losses have indefinite lives. We received reassessments from the Canada Revenue Agency (“CRA”) related to a transfer pricing matter impacting years 2003 through 2013. During 2016, we reached an agreement to settle the transfer pricing matter for years 2003 through 2013 and recorded a net discrete tax benefit of $8 million . We are subject to the continuous examination of our income tax returns by the IRS and other authorities. The IRS is currently examining our U.S. corporation income tax returns for 2007 through 2009 and may issue a Revenue Agent Report during the first quarter of 2017. We believe that adequate amounts have been reserved for any adjustments that may ultimately result from these examinations. The following table summarizes the activity related to our gross unrecognized tax benefits for the last three years: Years Ended March 31, (In millions) 2016 2015 2014 Unrecognized tax benefits at beginning of period $ 616 $ 647 $ 560 Additions based on tax positions related to prior years 116 62 106 Reductions based on tax positions related to prior years (62 ) (18 ) (23 ) Additions based on tax positions related to current year 28 27 23 Reductions based on settlements (141 ) (65 ) (4 ) Reductions based on the lapse of the applicable statutes of limitations (6 ) (12 ) (7 ) Exchange rate fluctuations 4 (25 ) (8 ) Unrecognized tax benefits at end of period $ 555 $ 616 $ 647 As of March 31, 2016 , we had $555 million of unrecognized tax benefits, of which $380 million would reduce income tax expense and the effective tax rate, if recognized. During the next twelve months, it is reasonably possible that audit resolutions and the expiration of statutes of limitations could potentially reduce our unrecognized tax benefits by up to $125 million . However, this amount may change as we continue to have ongoing negotiations with various taxing authorities throughout the year. We report interest and penalties on income taxes as income tax expense. We recognized income tax expense of $12 million in 2016, income tax benefit of $24 million in 2015 and income tax expense of $48 million in 2014, related to interest and penalties in our consolidated statements of operations. The income tax benefit for interest and penalties recognized in 2015 was primarily due to the lapses of statutes of limitations. As of March 31, 2016 and 2015, we had accrued $77 million and $122 million cumulatively in interest and penalties on unrecognized tax benefits. We file income tax returns in the U.S. federal jurisdiction, various U.S. state jurisdictions and various foreign jurisdictions. We are subject to audit by the IRS for fiscal years 2007 through the current fiscal year. We are generally subject to audit by taxing authorities in various U.S. states and in foreign jurisdictions for fiscal years 2006 through the current fiscal year.

Discontinued Operations

Discontinued Operations	12 Months Ended
	Mar. 31, 2016
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	During the second quarter of 2016, we sold our ZEE Medical business within our Distribution Solutions segment for total proceeds of $134 million and recorded a pre-tax gain of $52 million ( $29 million after-tax) from this sale. During the first quarter of 2016, we also sold our nurse triage business within our Technology Solutions segment for net sale proceeds of $84 million and recorded a pre-tax gain of $51 million ( $38 million after-tax) from the sale. These divestitures did not meet the criteria to qualify as discontinued operations under the amended accounting guidance, which became effective for us in the first quarter of 2016. Accordingly, pre-tax gains from both divestitures were recorded in operating expenses within continuing operations of our consolidated statements of operations. Pre and after-tax income of these businesses were not material for the year ended March 31, 2016. Discontinued Operations Brazil Distribution Business During the fourth quarter of 2015, we committed to a plan to sell our Brazilian pharmaceutical distribution business, which we acquired through our February 2014 acquisition of Celesio, from our Distribution Solutions segment. Accordingly, the results of operations and cash flows of this business are classified as discontinued operations for all periods presented in our consolidated financial statements. During the fourth quarter of 2015, we recorded $241 million of non-cash pre-tax ( $235 million after-tax) impairment charges to reduce the carrying value of this Brazilian distribution business to its estimated fair value less costs to sell. The impairment charge reduced the carrying value of property, plant and equipment, other long-lived assets and goodwill by $31 million . The remaining difference between the business’ fair value and carrying value of $210 million was recorded as a liability and was included in other accrued liabilities in our consolidated balance sheet at March 31, 2015. Cumulative foreign currency translation losses of $17 million were included in the assessment of this business’ carrying value for purposes of calculating the impairment charge. Cumulative foreign currency translation losses, net of tax, were included in Accumulated Other Comprehensive Income on our consolidated balance sheet at March 31, 2015. On January 31, 2016, we entered into an agreement to sell our Brazilian pharmaceutical distribution business to a third party. The sale is expected to be completed during the first half of 2017, subject to regulatory approval and customary closing conditions. We expect to recognize an after-tax charge of approximately $80 million to $100 million upon the disposition of the business within discontinued operations as a result of settlement of certain indemnification matters. Technology Solutions Businesses In 2014, we committed to a plan to sell our International Technology and our Hospital Automation businesses from our Technology Solutions segment. As required, in 2014, we classified the results of operations and cash flows of these businesses as discontinued operations for all applicable periods presented in our consolidated financial statements. Depreciation and amortization expense was not recognized from the date these businesses were classified as held for sale. During the third quarter of 2014, we completed the sale of our Hospital Automation business and recorded a pre-tax and after-tax loss of $5 million and $7 million . During the third quarter of 2014, we recorded an $80 million non-cash pre-tax and after-tax impairment charge to reduce the carrying value of our International Technology business to its estimated fair value less costs to sell. The impairment charge was primarily attributed to goodwill and other long-lived assets and as a result, there was no tax benefit associated with this charge. During the first quarter of 2015, we decided to retain the workforce business within our International Technology business. This business consists of workforce management solutions for the National Health Service in the United Kingdom. We reclassified the workforce business, which had been designated as a discontinued operation since the first quarter of 2014, to continuing operations in the first quarter of 2015. As a result, during the first quarter of 2015, we recorded non-cash pre-tax charges of $34 million ( $27 million after-tax) primarily associated with depreciation and amortization expense for 2014 when the business was classified as held for sale. The non-cash charge was recorded in our consolidated statement of operations primarily in cost of sales. During the second quarter of 2015, we completed the sale of a software business within our International Technology business and recorded a pre-tax and after-tax loss of $6 million . A summary of results of discontinued operations is as follows: Years Ended March 31, (In millions) 2016 2015 2014 Revenues $ 1,603 $ 2,196 $ 637 Loss from discontinued operations $ (24 ) $ (321 ) $ (177 ) Loss on sale — (6 ) (5 ) Loss from discontinued operations before income tax (24 ) (327 ) (182 ) Income tax (expense) benefit (8 ) 28 26 Loss from discontinued operations, net of tax $ (32 ) $ (299 ) $ (156 ) A summary of carrying amounts of major classes of assets and liabilities included as part of discontinued operations is as follow: March 31, (In millions) 2016 2015 Receivables, net $ 289 $ 314 Inventories, net 266 254 Other assets 80 92 Total assets of discontinued operations (1) 635 660 Drafts and account payable 264 209 Short-term borrowings 142 126 Other liabilities 254 328 Total liabilities of discontinued operations (1) $ 660 $ 663 (1) Assets and liabilities of discontinued operations are included under the captions “Prepaid expenses and other” and “Other accrued liabilities” within our consolidated balance sheets.

Noncontrolling Interests and Re

Noncontrolling Interests and Redeemable Noncontrolling Interests	12 Months Ended
	Mar. 31, 2016
Noncontrolling Interest [Abstract]
Noncontrolling Interests and Redeemable Noncontrolling Interests	Noncontrolling Interests and Redeemable Noncontrolling Interests Domination and Profit and Loss Transfer Agreement On May 22, 2014, Celesio and McKesson, through its wholly-owned subsidiary, Celesio Holdings Deutschland GmbH & Co. KGaA (“Celesio Holdings,” formerly known as McKesson Deutschland GmbH & Co. KGaA or Dragonfly GmbH & Co. KGaA), entered into the domination and profit and loss transfer agreement (the “Domination Agreement”). The Domination Agreement was approved at the general shareholders’ meeting of Celesio on July 15, 2014, approved by the Stuttgart Higher Regional Court for registration on December 2, 2014, and was registered in the commercial register of Celesio at the local court of Stuttgart on December 2, 2014. As a result, McKesson obtained the ability to pursue integration of the two companies on December 2, 2014. All litigation relating to the registration of the Domination Agreement has been resolved with no adverse impact on the effectiveness of the Domination Agreement or McKesson’s ability to direct the activities of Celesio. Upon the effectiveness of the Domination Agreement, Celesio subordinated its management to McKesson and undertook to transfer all of its annual profits to McKesson, and McKesson undertook to compensate any annual losses incurred by Celesio and to grant, subject to a potential court review, the noncontrolling shareholders of Celesio (i) an annual recurring compensation of €0.83 per Celesio share (“Compensation Amount”), (ii) a one-time dividend for Celesio’s fiscal year ended December 31, 2014 of €0.83 per Celesio share reduced accordingly for any dividend paid by Celesio in relation to its fiscal year ended December 31, 2014 (“Guaranteed Dividend”) and (iii) a right to put (“Put Right”) their Celesio shares at €22.99 per share increased annually for interest in the amount of 5 percentage points above a base rate published by the German Bundesbank semiannually, less any Compensation Amount or Guaranteed Dividend already paid in respect of the relevant time period (“Put Amount”). The Domination Agreement does not have an expiration date and can be terminated by McKesson without cause in writing no earlier than March 31, 2020. Under the Domination Agreement, the noncontrolling shareholders of Celesio ceased to participate in their percentage ownership of Celesio’s profits and losses, but instead became entitled to receive the one-time Guaranteed Dividend in December 2014 and the Compensation Amount from January 2015. As a result, during 2016 and 2015, we recorded a total attribution of net income to the noncontrolling shareholders of Celesio of $44 million and $62 million . All amounts were recorded in our consolidated statement of operations within the caption, “Net Income Attributable to Noncontrolling Interests,” and the corresponding liability balance was recorded within other accrued liabilities on our consolidated balance sheet. Appraisal Proceedings Subsequent to the Domination Agreement’s registration, certain noncontrolling shareholders of Celesio initiated appraisal proceedings (“Appraisal Proceedings”) with the Stuttgart Regional Court to challenge the Compensation Amount, Guaranteed Dividend and/or Put Amount. As long as any Appraisal Proceedings are pending, the Compensation Amount, Guaranteed Dividend and/or Put Amount will be paid as specified currently in the Domination Agreement. If any such Appraisal Proceedings result in an adjustment to the Compensation Amount, Guaranteed Dividend and/or Put Amount, Celesio Holdings would be required to make certain additional payments for any shortfall to all Celesio noncontrolling shareholders who previously received the Guaranteed Dividend, Compensation Amount and/or Put Amount. The Put Right specified in the Domination Agreement may be exercised until two months after the announcement regarding the end of the Appraisal Proceedings. In addition, if the Domination Agreement is terminated, the Put Right may be exercised for a two -month period after the date of termination. Redeemable Noncontrolling Interests Upon the effectiveness of the Domination Agreement, the noncontrolling interests in Celesio became redeemable as a result of the Put Right. Accordingly, the carrying value of noncontrolling interests related to Celesio of $1.5 billion was reclassified from “Total Equity” to “Redeemable Noncontrolling Interests” on our consolidated balance sheet during the third quarter of 2015. The balance of redeemable noncontrolling interests is reported at the greater of its carrying value or its maximum redemption value at each reporting date. The redemption value is the Put Amount adjusted for exchange rate fluctuations each period. At March 31, 2016 and 2015, the carrying value of redeemable noncontrolling interests of $1.41 billion and $1.39 billion exceeded the maximum redemption value of $1.28 billion and $1.21 billion . At March 31, 2016 and 2015, we owned approximately 76% of Celesio’s outstanding common shares. Changes in noncontrolling interests and redeemable noncontrolling interests were as follows: (In millions) Noncontrolling interests Redeemable Noncontrolling Interests Balance, March 31, 2014 $ 1,796 $ — Net income attributable to noncontrolling interests (1) 5 62 Other comprehensive loss (174 ) (105 ) Purchase of noncontrolling interests (2) (3) (4) (60 ) (9 ) Reclassification from Total Equity to Redeemable Noncontrolling Interests (5) (1,500 ) 1,500 Reclassification of guaranteed dividends and recurring compensation to other accrued liabilities — (62 ) Other 17 — Balance, March 31, 2015 84 1,386 Net income attributable to noncontrolling interests (1) 8 44 Other comprehensive loss — 20 Reclassification of recurring compensation to other accrued liabilities — (44 ) Other (8 ) — Balance, March 31, 2016 $ 84 $ 1,406 (1) Redeemable noncontrolling interests for 2015 include the Guaranteed Dividend of $50 million and the Compensation Amount of $12 million , and for 2016 include the Compensation Amount of $44 million . (2) Includes $35 million decrease in noncontrolling interests resulting from the April 2014 completion of McKesson’s tender offer for approximately 1 million additional Celesio shares. (3) Includes $25 million decrease in noncontrolling interests resulting from the July 2014 purchase of the remaining ownership interests in a wholesale distributor in Brazil. (4) Decrease in redeemable noncontrolling interests reflects the exercise of the Put Right by the noncontrolling shareholders of Celesio. (5) Includes net foreign currency losses of $138 million attributable to noncontrolling interests.

Earnings Per Common Share

Earnings Per Common Share	12 Months Ended
	Mar. 31, 2016
Earnings Per Share [Abstract]
Earnings Per Common Share	Earnings Per Common Share Basic earnings per common share are computed by dividing net income by the weighted average number of common shares outstanding during the reporting period. Diluted earnings per common share are computed similar to basic earnings per common share except that it reflects the potential dilution that could occur if dilutive securities or other obligations to issue common stock were exercised or converted into common stock. The computations for basic and diluted earnings per common share are as follows: Years Ended March 31, (In millions, except per share amounts) 2016 2015 2014 Income from continuing operations $ 2,342 $ 1,842 $ 1,414 Net (income) loss attributable to noncontrolling interests (52 ) (67 ) 5 Income from continuing operations attributable to McKesson 2,290 1,775 1,419 Loss from discontinued operations, net of tax (32 ) (299 ) (156 ) Net income attributable to McKesson $ 2,258 $ 1,476 $ 1,263 Weighted average common shares outstanding: Basic 230 232 229 Effect of dilutive securities: Options to purchase common stock 1 1 1 Restricted stock units 2 2 3 Diluted 233 235 233 Earnings (loss) per common share attributable to McKesson: (1) Diluted Continuing operations $ 9.84 $ 7.54 $ 6.08 Discontinued operations (0.14 ) (1.27 ) (0.67 ) Total $ 9.70 $ 6.27 $ 5.41 Basic Continuing operations $ 9.96 $ 7.66 $ 6.19 Discontinued operations (0.14 ) (1.29 ) (0.68 ) Total $ 9.82 $ 6.37 $ 5.51 (1) Certain computations may reflect rounding adjustments. Potentially dilutive securities include outstanding stock options, restricted stock units, and performance-based and other restricted stock units. Approximately 2 million , 1 million and 2 million of potentially dilutive securities were excluded from the computations of diluted net earnings per common share in 2016 , 2015 and 2014 , as they were anti-dilutive.

Receivables, Net

Receivables, Net	12 Months Ended
	Mar. 31, 2016
Receivables, Net, Current [Abstract]
Receivables, Net	Receivables, Net March 31, (In millions) 2016 2015 Customer accounts $ 14,519 $ 13,117 Other 3,711 2,965 Total 18,230 16,082 Allowances (250 ) (168 ) Net $ 17,980 $ 15,914 Other receivables primarily include amounts due from suppliers and customer unbilled receivables. The allowances are primarily for estimated uncollectible accounts.

Property, Plant and Equipment,

Property, Plant and Equipment, Net	12 Months Ended
	Mar. 31, 2016
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Net	Property, Plant and Equipment, Net March 31, (In millions) 2016 2015 Land $ 228 $ 207 Building, machinery, equipment and other 3,556 3,237 Total property, plant and equipment 3,784 3,444 Accumulated depreciation (1,506 ) (1,399 ) Property, plant and equipment, net $ 2,278 $ 2,045

Goodwill and Intangible Assets,

Goodwill and Intangible Assets, Net	12 Months Ended
	Mar. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets, Net	Goodwill and Intangible Assets, Net Changes in the carrying amount of goodwill were as follows: (In millions) Distribution Solutions Technology Solutions Total Balance, March 31, 2014 $ 8,078 $ 1,849 $ 9,927 Goodwill acquired 93 — 93 Amount reclassified to assets held-for-sale (14 ) (1 ) (15 ) Acquisition accounting, transfers and other adjustments 625 — 625 Foreign currency translation adjustments, net (788 ) (25 ) (813 ) Balance, March 31, 2015 $ 7,994 $ 1,823 $ 9,817 Goodwill acquired 21 — 21 Acquisition accounting, transfers and other adjustments 8 — 8 Goodwill disposed (59 ) (27 ) (86 ) Foreign currency translation adjustments, net 23 3 26 Balance, March 31, 2016 $ 7,987 $ 1,799 $ 9,786 As of March 31, 2016 and 2015, the accumulated goodwill impairment losses were $36 million in our Technology Solutions segment. Information regarding intangible assets is as follows: March 31, 2016 March 31, 2015 (Dollars in millions) Weighted Average Remaining Amortization Period (Years) Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Customer lists 7 $ 2,652 $ (1,324 ) $ 1,328 $ 2,683 $ (1,116 ) $ 1,567 Service agreements 14 959 (269 ) 690 957 (215 ) 742 Pharmacy licenses 25 857 (121 ) 736 874 (65 ) 809 Trademarks and trade names 14 314 (96 ) 218 315 (82 ) 233 Technology 2 195 (182 ) 13 213 (184 ) 29 Other 3 163 (127 ) 36 162 (101 ) 61 Total $ 5,140 $ (2,119 ) $ 3,021 $ 5,204 $ (1,763 ) $ 3,441 Amortization expense of intangible assets was $431 million , $494 million and $319 million for 2016 , 2015 and 2014 . Estimated annual amortization expense of intangible assets is as follows: $355 million , $337 million , $308 million , $281 million and $262 million for 2017 through 2021 , and $1,478 million thereafter. All intangible assets were subject to amortization as of March 31, 2016 and 2015 .

Capitalized Software Held for S

Capitalized Software Held for Sale, Net	12 Months Ended
	Mar. 31, 2016
Capitalized Computer Software, Net [Abstract]
Capitalized Software Held For Sale, Net	Capitalized Software Held for Sale, Net Changes in the carrying amount of capitalized software held for sale, net, which is included in other assets in the consolidated balance sheets, were as follows: Years Ended March 31, (In millions) 2016 2015 2014 Balance, at beginning of period $ 91 $ 103 $ 126 Amounts capitalized 30 34 40 Amortization expense (37 ) (40 ) (50 ) Impairment charges — — (12 ) Disposal (5 ) — — Foreign currency translations adjustments, net (1 ) (6 ) (1 ) Balance, at end of period $ 78 $ 91 $ 103

Debt and Financing Activities

Debt and Financing Activities	12 Months Ended
	Mar. 31, 2016
Debt Disclosure [Abstract]
Debt and Financing Activities	Debt and Financing Activities Long-term debt consisted of the following: March 31, (In millions) 2016 2015 U.S. Dollar notes (1) Floating Rate Notes due September 10, 2015 $ — $ 400 0.95% Notes due December 4, 2015 — 500 3.25% Notes due March 1, 2016 — 600 5.70% Notes due March 1, 2017 500 500 1.29% Notes due March 10, 2017 700 700 1.40% Notes due March 15, 2018 500 499 7.50% Notes due February 15, 2019 350 349 2.28% Notes due March 15, 2019 1,100 1,100 4.75% Notes due March 1, 2021 599 599 2.70% Notes due December 15, 2022 400 400 2.85% Notes due March 15, 2023 400 400 3.80% Notes due March 15, 2024 1,100 1,100 7.65% Debentures due March 1, 2027 175 175 6.00% Notes due March 1, 2041 493 493 4.88% Notes due March 15, 2044 800 800 Foreign currency notes (2) 4.00% Bonds due October 18, 2016 403 388 4.50% Bonds due April 26, 2017 583 563 Lease and other obligations 44 143 Total debt 8,147 9,709 Less current portion (1,612 ) (1,529 ) Total long-term debt $ 6,535 $ 8,180 (1) Interest on these notes is payable semiannually each year. These notes are unsecured and unsubordinated obligations of the Company. (2) Interest on these Euro-denominated bonds is due annually each year. Long-Term Debt Our long-term debt includes both U.S. dollar and foreign currency denominated borrowings. At March 31, 2016 and March 31, 2015, $8,147 million and $9,709 million of total debt were outstanding, of which $1,612 million and $1,529 million were included under the caption “Current portion of long-term debt” within our consolidated balance sheets. On March 5, 2014, we issued floating rate notes due September 10, 2015 in an aggregate principal amount of $400 million (“Floating Rate Notes”), 1.29% notes due March 10, 2017 in an aggregate principal amount of $700 million (“2017 Notes”), 2.28% notes due March 15, 2019 in an aggregate principal amount of $1,100 million (“2019 Notes”), 3.80% notes due March 15, 2024 in an aggregate principal amount of $1,100 million (“2024 Notes”) and 4.88% notes due March 15, 2044 in an aggregate principal amount of $800 million (“2044 Notes”). Interest on the 2017 Notes is payable on March 10 and September 10 of each year. Interest on the 2019 Notes, the 2024 Notes and the 2044 Notes is payable on March 15 and September 15 of each year. We utilized the net proceeds from the issuance of these notes (each note constitutes a “Series”) of $4,068 million , net of discounts and offering expenses, to repay the borrowings under our 2014 Bridge Loan, as further described below. Each Series constitutes an unsecured and unsubordinated obligation of the Company and ranks equally with all of the Company’s existing and, from time-to-time, future unsecured and unsubordinated indebtedness outstanding. Each Series is governed by materially similar indentures and officers’ certificate specifying certain terms of each Series. Upon 30 days notice to holders of a Series, we may redeem that Series at any time prior to maturity, in whole or in part, for cash at redemption prices that include accrued and unpaid interest and a make-whole premium, as specified in the indenture and officers’ certificate relating to that Series. In the event of the occurrence of both (1) a change of control of the Company and (2) a downgrade of a Series below an investment grade rating by each of Fitch Ratings, Moody’s Investors Service, Inc. and Standard & Poor’s Ratings Services within a specified period, an offer must be made to purchase that Series from the holders at a price in cash equal to 101% of the then outstanding principal amount of that Series, plus accrued and unpaid interest to, but not including, the date of repurchase. The indenture and the related officers’ certificate for each Series, subject to the exceptions and in compliance with the conditions as applicable, specify that we may not incur liens, enter into sale and leaseback transactions or consolidate, merge or sell all or substantially all of our assets. The indentures also contain customary events of default provisions. Senior Bridge Term Loan Facilities In connection with our acquisition of Celesio, in January 2014, we entered into a $5.5 billion 364 ‑day unsecured Senior Bridge Term Loan Agreement (the “2014 Bridge Loan”) under terms substantially similar to those in our existing revolving credit facility. On February 4, 2014, we borrowed $4,957 million under this facility with such proceeds and cash on hand used to fund the acquisition of Celesio. On March 10, 2014, we repaid $4,076 million of the 2014 Bridge Loan borrowings with funds obtained from the issuance of long-term debt. On March 11, 2014, we repaid the remaining balance of the 2014 Bridge Loan borrowings using funds drawn on our Accounts Receivable Sales Facility and cash on hand. On April 30, 2014, the commitments under the 2014 Bridge Loan automatically terminated upon the settlement of the tender offers for the remaining common shares of Celesio. During the time it was outstanding, the 2014 Bridge Loan borrowings bore interest at 1.39% per annum, based on the London Interbank Offered Rate plus a margin based on the Company’s credit rating. Interest expense for 2014 included a total of $46 million of fees related to the 2014 Bridge Loan and a bridge loan agreement entered into during the third quarter of 2014 in anticipation of an earlier acquisition of Celesio. Other Information Scheduled future payments of long-term debt are $1,612 million in 2017 , $1,092 million in 2018 , $1,458 million in 2019 , $3 million in 2020 , $2 million in 2021 and $3,980 million thereafter. In 2016, we repaid our $400 million floating rate notes due September 10, 2015 at maturity, $500 million 0.95% notes due December 4, 2015 at maturity and $600 million 3.25% notes due March 1, 2016 at maturity. In 2014, we repaid our $350 million 6.50% Notes due February 15, 2014. Revolving Credit Facilities During the third quarter of 2016, we entered into a syndicated $3.5 billion five -year senior unsecured revolving credit facility (the “Global Facility”). The Global Facility has a $3.15 billion aggregate sublimit of availability in Canadian dollars, British pound sterling and Euros. The remaining terms and conditions of the Global Facility are substantially similar to those previously in place under the $1.3 billion revolving credit facility which was terminated in October 2015. There were no borrowings outstanding under this facility as of March 31, 2016. The Global Facility contains a financial covenant which obligates the Company to maintain a debt to capital ratio of no greater than 65% and other customary investment grade covenants. If we do not comply with these covenants, our ability to use the Global Facility may be suspended and repayment of any outstanding balances under the Global Facility may be required. At March 31, 2016, we were in compliance with all covenants. At March 31, 2015, we had a syndicated $1.3 billion five -year senior unsecured revolving credit facility with the original expiration date in September 2016, as well as a syndicated €500 million five -year senior unsecured revolving credit facility with the original expiration date in February 2018. Both revolving credit facilities were terminated in connection with the execution of a new $3.5 billion global facility in October 2015, as discussed above. There were no borrowings outstanding under these facilities during the last three years, and as of March 31, 2015. We also maintain bilateral credit lines primarily denominated in Euros with a total committed and uncommitted balance of $427 million . These credit lines have interest rates ranging from 0.18% to 6.00% . During 2016 and 2015, we borrowed $641 million and $225 million and repaid $635 million and $267 million under these credit lines primarily related to short‑term borrowings. Borrowings and repayments during 2014 were not material. As of March 31, 2016 and 2015, there were $28 million and $29 million outstanding under these credit lines. Accounts Receivable Facilities Following the execution of the Global Facility, we also terminated an accounts receivable sales facility (the “AR Facility”) with a committed balance of $1.35 billion during the third quarter of 2016. There were no borrowings outstanding under the AR Facility during 2016 and 2015. In 2014, we borrowed $550 million under the AR Facility and repaid $550 million . At March 31, 2015, there were no secured borrowings and related securitized accounts receivable outstanding under the AR Facility. The AR Facility contained requirements relating to the performance of the accounts receivable and covenants relating to the Company. If we did not comply with these covenants, our ability to use the AR Facility would have been suspended and repayment of any outstanding balances under the AR Facility would have been required. At March 31, 2015, we were in compliance with all covenants. We also have Accounts Receivable Factoring Facilities (the “Factoring Facilities”) denominated in foreign currencies. Transactions under these facilities are accounted for as secured borrowings and have interest rates ranging from 0.85% to 1.26% . During 2016, 2015 and 2014, we borrowed $919 million , $2,875 million and $570 million and repaid $1,055 million , $2,908 million and $575 million in short-term borrowings under these facilities. At March 31, 2016 and 2015, there were $7 million and $135 million in secured borrowings outstanding under these facilities. All of the Factoring Facilities expired through April 2016. Commercial Paper We maintain a commercial paper program to support our working capital requirements and for other general corporate purposes. In November 2015, we replaced the existing program with a new commercial paper program through which the Company can issue up to $3.5 billion in outstanding notes. There were no material commercial paper issuances during the last three years and no amounts outstanding at March 31, 2016.

Variable Interest Entities

Variable Interest Entities	12 Months Ended
	Mar. 31, 2016
Variable Interest Entity, Not Primary Beneficiary, Disclosures [Abstract]
Variable Interest Entities	Variable Interest Entities We evaluate our ownership, contractual and other interests in entities to determine if they are variable interest entities (“VIEs”), if we have a variable interest in those entities and the nature and extent of those interests. These evaluations are highly complex and involve judgment and the use of estimates and assumptions based on available historical information and management’s judgment, among other factors. Based on our evaluations, if we determine we are the primary beneficiary of such VIEs, we consolidate such entities into our financial statements. Consolidated Variable Interest Entities We consolidate VIEs when we have the power to direct the activities that most significantly impact the VIE’s economic performance and the obligation to absorb losses or the right to receive benefits of the VIE and, as a result, are considered the primary beneficiary of the VIE. We consolidate certain single-lessee leasing entities where we, as the lessee, have the majority risk of the leased assets due to our minimum lease payment obligations to these leasing entities. As a result of absorbing this risk, the leases provide us with the power to direct the operations of the leased properties and the obligation to absorb losses or the right to receive benefits of the entity. Consolidated VIEs have an immaterial impact on our consolidated statements of operations and cash flows. Total assets and liabilities included in our consolidated balance sheet for these VIEs were $119 million and $44 million at March 31, 2016 and $144 million and $51 million at March 31, 2015. Investments in Unconsolidated Variable Interest Entities We are involved with VIEs which we do not consolidate because we do not have the power to direct the activities that most significantly impact their economic performance and thus are not considered the primary beneficiary of the entities. Our relationships include equity investments and lending, leasing, contractual or other relationships with the VIEs. Our most significant relationships are with oncology and other specialty practices. Under these practice arrangements, we generally own or lease all of the real estate and equipment used by the affiliated practices and manage the practices’ administrative functions. We also have relationships with certain pharmacies in Europe with whom we may provide financing, have equity ownership and/or a supply agreement whereby we supply the vast majority of the pharmacies’ purchases. Our maximum exposure to loss (regardless of probability) as a result of all unconsolidated VIEs were $1.1 billion and $1.2 billion at March 31, 2016 and 2015 , which primarily represents the value of intangible assets related to service agreements, equity investments and lease and loan receivables. These amounts exclude the customer loan guarantees discussed in Financial Note 23, “Financial Guarantees and Warranties.” We believe that there is no material loss exposure on these assets or from these relationships.

Pension Benefits

Pension Benefits	12 Months Ended
	Mar. 31, 2016
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]
Pension Benefits	Pension Benefits We maintain a number of qualified and nonqualified defined benefit pension plans and defined contribution plans for eligible employees. Defined Benefit Pension Plans Eligible U.S. employees who were employed by the Company as of December 31, 1995 are covered under the Company-sponsored defined benefit retirement plan. In 1997, the plan was amended to freeze all plan benefits as of December 31, 1996. Benefits for the defined benefit retirement plan are based primarily on age of employees at date of retirement, years of creditable service and the average of the highest 60 months of pay during the 15 years prior to the plan freeze date. We also have defined benefit pension plans for eligible employees outside of the U.S., as well as an unfunded nonqualified supplemental defined benefit plan for certain U.S. executives. Our non-U.S. defined benefit pension plans cover eligible employees located predominantly in Norway, United Kingdom and Germany. Benefits for these plans are based primarily on each employee’s final salary, with annual adjustments for inflation. The obligations in Norway are largely related to the state-regulated pension plan which is managed by the Norwegian Public Service Pension Fund (“SPK”). According to the terms of the SPK, the plan assets of state regulated plans in Norway must correspond very closely to the pension obligation calculated using the principles codified in Norwegian law. The shortfall may not exceed 1% of the obligation. If the shortfall exceeds this threshold, it must be remedied within two years. In the United Kingdom, we have subsidiaries that participate in a joint pension plan. This plan is largely funded by contractual trust arrangements that hold Company assets that may only be used to pay pension obligations. The Trustee Board decides on the minimum contribution to the plan in association with selected employees of the entity. A valuation is performed at regular intervals in order to determine the amount of the contribution and to ensure that the minimum contribution is made. The pension obligation in Germany is unfunded with the exception of the contractual trust arrangement used to fund pensions of Celesio’s Management Board. Defined benefit plan assets and obligations are measured as of the Company’s fiscal year-end. The net periodic expense for our pension plans, which includes net pension expense of Celesio beginning February 2014, is as follows: U.S. Plans Non-U.S. Plans Years Ended March 31, Years Ended March 31, (In millions) 2016 2015 2014 2016 2015 2014 Service cost - benefits earned during the year $ 4 $ 1 $ 4 $ 20 $ 16 $ 6 Interest cost on projected benefit obligation 18 19 19 24 34 11 Expected return on assets (19 ) (21 ) (20 ) (30 ) (30 ) (12 ) Amortization of unrecognized actuarial loss, prior service costs and net transitional obligation 42 19 32 3 3 4 Curtailment/settlement loss (gain) 2 — — — 6 (1 ) Net periodic pension expense $ 47 $ 18 $ 35 $ 17 $ 29 $ 8 The projected unit credit method is utilized in measuring net periodic pension expense over the employees’ service life for the pension plans. Unrecognized actuarial losses exceeding 10% of the greater of the projected benefit obligation or the market value of assets are amortized straight-line over the average remaining future service periods. Information regarding the changes in benefit obligations and plan assets for our pension plans is as follows: U.S. Plans Non-U.S. Plans Years Ended March 31, Years Ended March 31, (In millions) 2016 2015 2016 2015 Change in benefit obligations Benefit obligation at beginning of period (1) $ 583 $ 540 $ 963 $ 934 Service cost 4 1 20 16 Interest cost 18 19 24 34 Actuarial loss (gain) (13 ) 53 (64 ) 194 Benefit payments (54 ) (30 ) (35 ) (49 ) Amendments — — (2 ) (6 ) Expenses paid (3 ) — — — Foreign exchange impact and other — — (7 ) (160 ) Benefit obligation at end of period (1) $ 535 $ 583 $ 899 $ 963 Change in plan assets Fair value of plan assets at beginning of period $ 298 $ 300 $ 612 $ 590 Actual return on plan assets (3 ) 16 2 88 Employer and participant contributions 24 12 44 73 Benefits paid (54 ) (30 ) (35 ) (49 ) Expenses paid (3 ) — — — Foreign exchange impact and other — — (16 ) (90 ) Fair value of plan assets at end of period $ 262 $ 298 $ 607 $ 612 Funded status at end of period $ (273 ) $ (285 ) $ (292 ) $ (351 ) Amounts recognized on the balance sheet Assets $ — $ — $ 21 $ — Current liabilities (2 ) (17 ) (11 ) (6 ) Long-term liabilities (271 ) (268 ) (302 ) (345 ) Total $ (273 ) $ (285 ) $ (292 ) $ (351 ) (1) The benefit obligation is the projected benefit obligation. The following table provides the projected benefit obligation, accumulated benefit obligation and fair value of plan assets for all our pension plans with an accumulated benefit obligation in excess of plan assets. U.S. Plans Non-U.S. Plans March 31, March 31, (In millions) 2016 2015 2016 2015 Projected benefit obligation $ 535 $ 583 $ 899 $ 963 Accumulated benefit obligation 535 583 855 897 Fair value of plan assets 262 298 607 612 Amounts recognized in accumulated other comprehensive income (pre-tax) consist of: U.S. Plans Non-U.S. Plans March 31, March 31, (In millions) 2016 2015 2016 2015 Net actuarial loss $ 185 $ 220 $ 133 $ 175 Prior service credit — — (11 ) (6 ) Total $ 185 $ 220 $ 122 $ 169 Other changes in accumulated other comprehensive income (pre-tax) were as follows: U.S. Plans Non-U.S. Plans Years Ended March 31, Years Ended March 31, (In millions) 2016 2015 2014 2016 2015 2014 Net actuarial loss (gain) $ 9 $ 58 $ (31 ) $ (38 ) $ 117 $ 12 Prior service credit — — (8 ) (5 ) (8 ) — Amortization of: Net actuarial loss (44 ) (27 ) (32 ) (5 ) (5 ) (4 ) Prior service credit (cost) — 8 — 2 2 2 Foreign exchange impact and other — — (1 ) (1 ) (8 ) 4 Total recognized in other comprehensive loss (income) $ (35 ) $ 39 $ (72 ) $ (47 ) $ 98 $ 14 We expect to amortize $15 million of actuarial loss for the pension plans from stockholders’ equity to pension expense in 2017 . Comparable 2016 amounts were $1 million of prior service credit and $47 million of actuarial loss. Projected benefit obligations related to our unfunded U.S. plans were $175 million and $189 million at March 31, 2016 and 2015 . Pension obligations for our unfunded plans are based on the recommendations of independent actuaries. Projected benefit obligations relating to our unfunded non-U.S. plans were $272 million and $222 million at March 31, 2016 and 2015. Funding obligations for our non-U.S. plans vary based on the laws of each non-U.S. jurisdiction. Expected benefit payments, including assumed executive lump sum payments, for our pension plans are as follows: $59 million , $174 million , $110 million , $66 million and $65 million for 2017 to 2021 and $327 million for 2022 through 2026 . Expected benefit payments are based on the same assumptions used to measure the benefit obligations and include estimated future employee service. Expected contributions to be made for our pension plans are $15 million for 2017 . Weighted-average assumptions used to estimate the net periodic pension expense and the actuarial present value of benefit obligations were as follows: U.S. Plans Non-U.S. Plans Years Ended March 31, Years Ended March 31, 2016 2015 2014 2016 2015 2014 Net periodic pension expense Discount rates 3.36 % 3.74 % 3.39 % 2.36 % 3.85 % 3.95 % Rate of increase in compensation 4.00 4.00 4.00 2.80 3.11 2.66 Expected long-term rate of return on plan assets 6.75 7.25 7.25 4.87 5.39 5.71 Benefit obligation Discount rates 3.27 % 3.18 % 3.58 % 2.84 % 2.50 % 3.92 % Rate of increase in compensation 4.00 4.00 4.00 2.98 3.24 3.27 Our defined benefit pension plan liabilities are valued using a discount rate based on a yield curve developed from a portfolio of high quality corporate bonds rated AA or better whose maturities are aligned with the expected benefit payments of our plans. For March 31, 2016 , our U.S. defined benefit liabilities are valued using a weighted average discount rate of 3.27% , which represents an increase of 9 basis points from our 2015 weighted-average discount rate of 3.18% . Our non-U.S defined benefit pension plan liabilities are valued using a weighted-average discount rate of 2.84% , which represents an increase of 34 basis points from our 2015 weighted-average discount rate of 2.50% . Sensitivity to changes in the weighted-average discount rate for our pension plans is as follows: U.S. Plans Non-U.S. Plans (In millions) One Percentage Point Increase One Percentage Point Decrease One Percentage Point Increase One Percentage Point Decrease Increase (decrease) on projected benefit obligation $ (35) $ 41 $ (85) $ 101 Increase (decrease) on net periodic pension cost — — (4) 6 Plan Assets Investment Strategy : The overall objective for U. S. pension plan assets is to generate long-term investment returns consistent with capital preservation and prudent investment practices, with a diversification of asset types and investment strategies. Periodic adjustments are made to provide liquidity for benefit payments and to rebalance plan assets to their target allocations. The target allocations for U.S. plan assets at March 31, 2016 and 2015 are 50% equity investments, 45% fixed income investments including cash and cash equivalents and 5% real estate. Equity investments include common stock, preferred stock, and equity commingled funds. Fixed income investments include corporate bonds, government securities, mortgage-backed securities, asset-backed securities, other directly held fixed income investments, and fixed income commingled funds. The real estate investment is in a commingled real estate fund. For both U.S. and non-U.S. plan assets, the investment strategies are subject to local regulations and the asset/liability profiles of the plans in each individual country. Plan assets of the non-U.S. plans are broadly invested in a manner appropriate to the nature and duration of the expected future retirement benefits payable under the plans. Plan assets are primarily invested in high-quality corporate and government bond funds and equity securities. Assets are properly diversified to avoid excessive reliance on any particular asset, issuer or group of undertakings so as to avoid accumulations of risk in the portfolio as a whole. We develop the expected long-term rate of return assumption based on the projected performance of the asset classes in which plan assets are invested. The target asset allocation was determined based on the liability and risk tolerance characteristics of the plans and at times may be adjusted to achieve overall investment objectives. Fair Value Measurements: The following tables represent our pension plan assets as of March 31, 2016 and 2015 , using the fair value hierarchy by asset class. The fair value hierarchy has three levels based on the reliability of the inputs used to determine fair value. Level 1 refers to fair values determined based on unadjusted quoted prices in active markets for identical assets. Level 2 refers to fair values estimated using significant other observable inputs and Level 3 includes fair values estimated using significant unobservable inputs. U.S. Plans Non-U.S. Plans March 31, 2016 March 31, 2016 (In millions) Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Cash and cash equivalents $ 4 $ — $ — $ 4 $ 4 $ — $ — $ 4 Equity securities: Common and preferred stock 16 — — 16 — — — — Equity commingled funds — 165 — 165 6 150 — 156 Fixed income securities: Government securities — 12 — 12 23 68 — 91 Corporate bonds — 12 — 12 1 14 — 15 Mortgage-backed securities — 14 — 14 — — — — Asset-backed securities and other — 22 — 22 — — — — Fixed income commingled funds — — — — 66 120 — 186 Other: Real estate funds — — 17 17 — — 24 24 Other — — — — 21 107 3 131 Total $ 20 $ 225 $ 17 $ 262 $ 121 $ 459 $ 27 $ 607 U.S. Plans Non-U.S. Plans March 31, 2015 March 31, 2015 (In millions) Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Cash and cash equivalents $ 55 $ 1 $ — $ 56 $ 8 $ — $ — $ 8 Equity securities: Common and preferred stock 18 — — 18 — — — — Equity commingled funds — 138 — 138 7 149 — 156 Fixed income securities: Government securities — 14 — 14 26 53 — 79 Corporate bonds — 14 — 14 — 13 — 13 Mortgage-backed securities — 14 — 14 — — — — Asset-backed securities and other — 26 — 26 — — — — Fixed income commingled funds — — — — 64 127 — 191 Other: Real estate funds — — 18 18 — — 26 26 Other commingled funds — — — — — 13 — 13 Other — — — — 7 115 4 126 Total $ 73 $ 207 $ 18 $ 298 $ 112 $ 470 $ 30 $ 612 Cash and cash equivalents - Cash and cash equivalents include short-term investment funds that maintain daily liquidity and aim to have constant unit values of $1.00 . The funds invest in short-term fixed income securities and other securities with debt-like characteristics emphasizing short-term maturities and high credit quality. Directly held cash and cash equivalents are classified as Level 1 investments. Cash and cash equivalents include money market funds and other commingled funds, which have daily net asset values derived from the underlying securities; these are classified as Level 1 investments. Common and preferred stock - This investment class consists of common and preferred shares issued by U.S. and non-U.S. corporations. Common shares are traded actively on exchanges and price quotes are readily available. Preferred shares may not be actively traded. Holdings of common shares are generally classified as Level 1 investments. Preferred shares are classified as Level 2 investments. Equity commingled funds - Some equity investments are held in commingled funds, which have daily net asset values derived from quoted prices for the underlying securities in active markets; these are classified as Level 1 or Level 2 investments. Fixed income securities - Government securities consist of bonds and debentures issued by central governments or federal agencies; corporate bonds consist of bonds and debentures issued by corporations; mortgage-backed securities consist of debt obligations secured by a mortgage or pool of mortgages; and asset-backed securities primarily consist of debt obligations secured by an asset or pool of assets other than mortgages. Inputs to the valuation methodology include quoted prices for similar assets in active markets, and inputs that are observable for the asset, either directly or indirectly, for substantially the full term of the asset. Multiple prices and price types are obtained from pricing vendors whenever possible, enabling cross-provider price validations. Fixed income securities are generally classified as Level 1 or Level 2 investments. Fixed income commingled funds - Some fixed income investments are held in exchange traded or commingled funds, which have daily net asset values derived from the underlying securities; these are classified as Level 1 or 2 investments. Real estate funds - The value of the real estate funds is reported by the fund manager and is based on a valuation of the underlying properties. Inputs used in the valuation include items such as cost, discounted future cash flows, independent appraisals and market based comparable data. The real estate funds are classified as Level 3 investments. Other commingled funds - The other commingled funds are invested in equities, bonds, commodities, other alternative investments and cash and cash equivalents. These funds are valued based on the weekly net asset values derived from the quoted prices for the underlying securities in active markets and, for alternative investments, based on other valuation techniques. Other commingled funds are classified as Level 1 or Level 2 investments. Other - At March 31, 2016 and 2015, this includes $40 million and $39 million of plan asset value relating to the SPK. In principle, the SPK is organized as a pay-as-you-go system guaranteed by the Norwegian government as it holds no Company-owned assets to back the pension liabilities. The Company pays a pension premium used to fund the plan, which is paid directly to the Norwegian government who establishes an account for each participating employer to keep track of the financial status of the plan, including managing the contributions and the payments. Further, the investment return credited to this account is determined annually by the SPK based on the performance of long-term government bonds. The following table represents a reconciliation of Level 3 plan assets held during the years ended March 31, 2016 and 2015 : U.S. Plans Non-U.S. Plans (In millions) Real Estate Funds Total Real Estate Funds Other Total Balance at March 31, 2014 $ 16 $ 16 $ 7 $ 5 $ 12 Acquisitions — — — — — Unrealized gain on plan assets still held 2 2 1 — 1 Purchases, sales and settlements — — 18 (1 ) 17 Balance at March 31, 2015 $ 18 $ 18 $ 26 $ 4 $ 30 Acquisitions — — — — — Unrealized gain on plan assets still held 1 1 (2 ) (1 ) (3 ) Purchases, sales and settlements (2 ) (2 ) — — — Balance at March 31, 2016 $ 17 $ 17 $ 24 $ 3 $ 27 Multiemployer Plans The Company contributes to a number of multiemployer pension plans under the terms of collective-bargaining agreements that cover union-represented employees in the U.S. In 2016, we also contributed to the Pensjonsordningen for Apoteketaten (“POA”), a mandatory multiemployer pension scheme for our pharmacy employees in Norway, managed by the association of Norwegian Pharmacies. The risks of participating in these multiemployer plans are different from single-employer pension plans in the following aspects: (i) assets contributed to the multiemployer plan by one employer may be used to provide benefits to employees of other participating employers; (ii) if a participating employer stops contributing to the plan, the unfunded obligations of the plan may be borne by the remaining participating employers; and (iii) if the Company chooses to stop participating in some of its multiemployer plans, the Company may be required to pay those plans an amount based on the underfunded status of the plan, referred to as a withdrawal liability. Actions taken by other participating employers may lead to adverse changes in the financial condition of a multiemployer benefit plan and our withdrawal liability and contributions may increase. Contributions and amounts accrued for U.S. Plans were not material for the years ended March 31, 2016, 2015, and 2014. Contributions to the POA for non-U.S. Plans exceeding 5% of total plan contributions were $23 million , $24 million and $5 million in 2016, 2015 and 2014. Based on actuarial calculations, we estimate the funded status for our non-U.S. Plans to be approximately 66% as of March 31, 2016 . No amounts were accrued for liability associated with the POA as we have no intention to withdraw from the plan. Defined Contribution Plans We have a contributory profit sharing investment plan (“PSIP”) for U.S. eligible employees. Eligible employees may contribute to the PSIP up to 75% of their eligible compensation on a pre-tax or post-tax basis not to exceed IRS limits. The Company makes matching contributions in an amount equal to 100% of the employee’s first 3% of pay contributed and 50% for the next 2% of pay contributed. The Company also may make an additional annual matching contribution for each plan year to enable participants to receive a full match based on their annual contribution. The Company also contributed to non-U.S. plans that are available in certain countries. Contribution expenses for the PSIP and non-U.S. plans were $99 million , $103 million and $83 million for the years ended March 31, 2016 , 2015 , and 2014 . Postretirement Benefits We maintain a number of postretirement benefits, primarily consisting of healthcare and life insurance (“welfare”) benefits, for certain eligible U.S. employees. Eligible employees consist of those who retired before March 31, 1999 and those who retired after March 31, 1999, but were an active employee as of that date, after meeting other age-related criteria. We also provide postretirement benefits for certain U.S. executives. Defined benefit plan obligations are measured as of the Company’s fiscal year-end. The net periodic expense for our postretirement welfare benefits is as follows: Years Ended March 31, (In millions) 2016 2015 2014 Service cost - benefits earned during the year $ 1 $ 1 $ 2 Interest cost on accumulated benefit obligation 4 5 5 Amortization of unrecognized actuarial gain and prior service credit — (4 ) (1 ) Curtailment gain — — (2 ) Net periodic postretirement expense $ 5 $ 2 $ 4 Information regarding the changes in benefit obligations for our postretirement welfare plans is as follows: Years Ended March 31, (In millions) 2016 2015 Benefit obligation at beginning of period $ 118 $ 119 Service cost 1 1 Interest cost 4 5 Plan amendments (16 ) — Actuarial loss 3 5 Benefit payments (11 ) (12 ) Curtailment gain (1 ) — Benefit obligation at end of period $ 98 $ 118 The components of the amount recognized in accumulated other comprehensive income for the Company’s other postretirement benefits at March 31, 2016 and 2015 were net actuarial losses of $4 million and $1 million and net prior service credits of $16 million and $1 million . Other changes in benefit obligations recognized in other comprehensive income were net actuarial losses of $3 million in 2016 and $9 million in 2015 and net prior service credits of $16 million in 2016. We estimate that the amortization of the actuarial loss from stockholders’ equity to other postretirement expense in 2017 will be $1 million . Comparable 2016 amount was a gain of $1 million . Other postretirement benefits are funded as claims are paid. Expected benefit payments for our postretirement welfare benefit plans are as follows: $11 million , $9 million , $9 million , $8 million and $8 million for 2017 to 2021 and $34 million cumulatively for 2022 through 2026 . Expected benefit payments are based on the same assumptions used to measure the benefit obligations and include estimated future employee service. Expected contributions to be made for our postretirement welfare benefit plans are $11 million for 2017 . Weighted-average discount rates used to estimate postretirement welfare benefit expenses were 3.59% , 4.07% and 3.84% for 2016 , 2015 and 2014 . Weighted-average discount rates for the actuarial present value of benefit obligations were 3.68% , 3.61% and 4.08% for 2016 , 2015 and 2014 . Actuarial gain or loss for the postretirement welfare benefit plan is amortized to income or expense over a three -year period. The assumed healthcare cost trends used in measuring the accumulated postretirement benefit obligation were 6.50% and 6.75% for prescription drugs, 7.00 / 6.50% and 7.25 / 6.75% for ages pre- 65 /post- 65 medical and 5.00% for dental in 2016 and 2015 . For 2016 , 2015 and 2014 , a one-percentage-point increase or decrease in the assumed healthcare cost trend rate would not have a material impact on the postretirement benefit obligations. Pursuant to various collective bargaining agreements, we contribute to multiemployer health and welfare plans that cover union-represented employees. Our liability is limited to the contractual dollar obligations set forth by the collective bargaining agreements. Contributions to the plans and amounts accrued were not material for the years ended March 31, 2016 , 2015 , and 2014 .

Postretirement Benefits

Postretirement Benefits	12 Months Ended
	Mar. 31, 2016
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]
Postretirement Benefits	Pension Benefits We maintain a number of qualified and nonqualified defined benefit pension plans and defined contribution plans for eligible employees. Defined Benefit Pension Plans Eligible U.S. employees who were employed by the Company as of December 31, 1995 are covered under the Company-sponsored defined benefit retirement plan. In 1997, the plan was amended to freeze all plan benefits as of December 31, 1996. Benefits for the defined benefit retirement plan are based primarily on age of employees at date of retirement, years of creditable service and the average of the highest 60 months of pay during the 15 years prior to the plan freeze date. We also have defined benefit pension plans for eligible employees outside of the U.S., as well as an unfunded nonqualified supplemental defined benefit plan for certain U.S. executives. Our non-U.S. defined benefit pension plans cover eligible employees located predominantly in Norway, United Kingdom and Germany. Benefits for these plans are based primarily on each employee’s final salary, with annual adjustments for inflation. The obligations in Norway are largely related to the state-regulated pension plan which is managed by the Norwegian Public Service Pension Fund (“SPK”). According to the terms of the SPK, the plan assets of state regulated plans in Norway must correspond very closely to the pension obligation calculated using the principles codified in Norwegian law. The shortfall may not exceed 1% of the obligation. If the shortfall exceeds this threshold, it must be remedied within two years. In the United Kingdom, we have subsidiaries that participate in a joint pension plan. This plan is largely funded by contractual trust arrangements that hold Company assets that may only be used to pay pension obligations. The Trustee Board decides on the minimum contribution to the plan in association with selected employees of the entity. A valuation is performed at regular intervals in order to determine the amount of the contribution and to ensure that the minimum contribution is made. The pension obligation in Germany is unfunded with the exception of the contractual trust arrangement used to fund pensions of Celesio’s Management Board. Defined benefit plan assets and obligations are measured as of the Company’s fiscal year-end. The net periodic expense for our pension plans, which includes net pension expense of Celesio beginning February 2014, is as follows: U.S. Plans Non-U.S. Plans Years Ended March 31, Years Ended March 31, (In millions) 2016 2015 2014 2016 2015 2014 Service cost - benefits earned during the year $ 4 $ 1 $ 4 $ 20 $ 16 $ 6 Interest cost on projected benefit obligation 18 19 19 24 34 11 Expected return on assets (19 ) (21 ) (20 ) (30 ) (30 ) (12 ) Amortization of unrecognized actuarial loss, prior service costs and net transitional obligation 42 19 32 3 3 4 Curtailment/settlement loss (gain) 2 — — — 6 (1 ) Net periodic pension expense $ 47 $ 18 $ 35 $ 17 $ 29 $ 8 The projected unit credit method is utilized in measuring net periodic pension expense over the employees’ service life for the pension plans. Unrecognized actuarial losses exceeding 10% of the greater of the projected benefit obligation or the market value of assets are amortized straight-line over the average remaining future service periods. Information regarding the changes in benefit obligations and plan assets for our pension plans is as follows: U.S. Plans Non-U.S. Plans Years Ended March 31, Years Ended March 31, (In millions) 2016 2015 2016 2015 Change in benefit obligations Benefit obligation at beginning of period (1) $ 583 $ 540 $ 963 $ 934 Service cost 4 1 20 16 Interest cost 18 19 24 34 Actuarial loss (gain) (13 ) 53 (64 ) 194 Benefit payments (54 ) (30 ) (35 ) (49 ) Amendments — — (2 ) (6 ) Expenses paid (3 ) — — — Foreign exchange impact and other — — (7 ) (160 ) Benefit obligation at end of period (1) $ 535 $ 583 $ 899 $ 963 Change in plan assets Fair value of plan assets at beginning of period $ 298 $ 300 $ 612 $ 590 Actual return on plan assets (3 ) 16 2 88 Employer and participant contributions 24 12 44 73 Benefits paid (54 ) (30 ) (35 ) (49 ) Expenses paid (3 ) — — — Foreign exchange impact and other — — (16 ) (90 ) Fair value of plan assets at end of period $ 262 $ 298 $ 607 $ 612 Funded status at end of period $ (273 ) $ (285 ) $ (292 ) $ (351 ) Amounts recognized on the balance sheet Assets $ — $ — $ 21 $ — Current liabilities (2 ) (17 ) (11 ) (6 ) Long-term liabilities (271 ) (268 ) (302 ) (345 ) Total $ (273 ) $ (285 ) $ (292 ) $ (351 ) (1) The benefit obligation is the projected benefit obligation. The following table provides the projected benefit obligation, accumulated benefit obligation and fair value of plan assets for all our pension plans with an accumulated benefit obligation in excess of plan assets. U.S. Plans Non-U.S. Plans March 31, March 31, (In millions) 2016 2015 2016 2015 Projected benefit obligation $ 535 $ 583 $ 899 $ 963 Accumulated benefit obligation 535 583 855 897 Fair value of plan assets 262 298 607 612 Amounts recognized in accumulated other comprehensive income (pre-tax) consist of: U.S. Plans Non-U.S. Plans March 31, March 31, (In millions) 2016 2015 2016 2015 Net actuarial loss $ 185 $ 220 $ 133 $ 175 Prior service credit — — (11 ) (6 ) Total $ 185 $ 220 $ 122 $ 169 Other changes in accumulated other comprehensive income (pre-tax) were as follows: U.S. Plans Non-U.S. Plans Years Ended March 31, Years Ended March 31, (In millions) 2016 2015 2014 2016 2015 2014 Net actuarial loss (gain) $ 9 $ 58 $ (31 ) $ (38 ) $ 117 $ 12 Prior service credit — — (8 ) (5 ) (8 ) — Amortization of: Net actuarial loss (44 ) (27 ) (32 ) (5 ) (5 ) (4 ) Prior service credit (cost) — 8 — 2 2 2 Foreign exchange impact and other — — (1 ) (1 ) (8 ) 4 Total recognized in other comprehensive loss (income) $ (35 ) $ 39 $ (72 ) $ (47 ) $ 98 $ 14 We expect to amortize $15 million of actuarial loss for the pension plans from stockholders’ equity to pension expense in 2017 . Comparable 2016 amounts were $1 million of prior service credit and $47 million of actuarial loss. Projected benefit obligations related to our unfunded U.S. plans were $175 million and $189 million at March 31, 2016 and 2015 . Pension obligations for our unfunded plans are based on the recommendations of independent actuaries. Projected benefit obligations relating to our unfunded non-U.S. plans were $272 million and $222 million at March 31, 2016 and 2015. Funding obligations for our non-U.S. plans vary based on the laws of each non-U.S. jurisdiction. Expected benefit payments, including assumed executive lump sum payments, for our pension plans are as follows: $59 million , $174 million , $110 million , $66 million and $65 million for 2017 to 2021 and $327 million for 2022 through 2026 . Expected benefit payments are based on the same assumptions used to measure the benefit obligations and include estimated future employee service. Expected contributions to be made for our pension plans are $15 million for 2017 . Weighted-average assumptions used to estimate the net periodic pension expense and the actuarial present value of benefit obligations were as follows: U.S. Plans Non-U.S. Plans Years Ended March 31, Years Ended March 31, 2016 2015 2014 2016 2015 2014 Net periodic pension expense Discount rates 3.36 % 3.74 % 3.39 % 2.36 % 3.85 % 3.95 % Rate of increase in compensation 4.00 4.00 4.00 2.80 3.11 2.66 Expected long-term rate of return on plan assets 6.75 7.25 7.25 4.87 5.39 5.71 Benefit obligation Discount rates 3.27 % 3.18 % 3.58 % 2.84 % 2.50 % 3.92 % Rate of increase in compensation 4.00 4.00 4.00 2.98 3.24 3.27 Our defined benefit pension plan liabilities are valued using a discount rate based on a yield curve developed from a portfolio of high quality corporate bonds rated AA or better whose maturities are aligned with the expected benefit payments of our plans. For March 31, 2016 , our U.S. defined benefit liabilities are valued using a weighted average discount rate of 3.27% , which represents an increase of 9 basis points from our 2015 weighted-average discount rate of 3.18% . Our non-U.S defined benefit pension plan liabilities are valued using a weighted-average discount rate of 2.84% , which represents an increase of 34 basis points from our 2015 weighted-average discount rate of 2.50% . Sensitivity to changes in the weighted-average discount rate for our pension plans is as follows: U.S. Plans Non-U.S. Plans (In millions) One Percentage Point Increase One Percentage Point Decrease One Percentage Point Increase One Percentage Point Decrease Increase (decrease) on projected benefit obligation $ (35) $ 41 $ (85) $ 101 Increase (decrease) on net periodic pension cost — — (4) 6 Plan Assets Investment Strategy : The overall objective for U. S. pension plan assets is to generate long-term investment returns consistent with capital preservation and prudent investment practices, with a diversification of asset types and investment strategies. Periodic adjustments are made to provide liquidity for benefit payments and to rebalance plan assets to their target allocations. The target allocations for U.S. plan assets at March 31, 2016 and 2015 are 50% equity investments, 45% fixed income investments including cash and cash equivalents and 5% real estate. Equity investments include common stock, preferred stock, and equity commingled funds. Fixed income investments include corporate bonds, government securities, mortgage-backed securities, asset-backed securities, other directly held fixed income investments, and fixed income commingled funds. The real estate investment is in a commingled real estate fund. For both U.S. and non-U.S. plan assets, the investment strategies are subject to local regulations and the asset/liability profiles of the plans in each individual country. Plan assets of the non-U.S. plans are broadly invested in a manner appropriate to the nature and duration of the expected future retirement benefits payable under the plans. Plan assets are primarily invested in high-quality corporate and government bond funds and equity securities. Assets are properly diversified to avoid excessive reliance on any particular asset, issuer or group of undertakings so as to avoid accumulations of risk in the portfolio as a whole. We develop the expected long-term rate of return assumption based on the projected performance of the asset classes in which plan assets are invested. The target asset allocation was determined based on the liability and risk tolerance characteristics of the plans and at times may be adjusted to achieve overall investment objectives. Fair Value Measurements: The following tables represent our pension plan assets as of March 31, 2016 and 2015 , using the fair value hierarchy by asset class. The fair value hierarchy has three levels based on the reliability of the inputs used to determine fair value. Level 1 refers to fair values determined based on unadjusted quoted prices in active markets for identical assets. Level 2 refers to fair values estimated using significant other observable inputs and Level 3 includes fair values estimated using significant unobservable inputs. U.S. Plans Non-U.S. Plans March 31, 2016 March 31, 2016 (In millions) Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Cash and cash equivalents $ 4 $ — $ — $ 4 $ 4 $ — $ — $ 4 Equity securities: Common and preferred stock 16 — — 16 — — — — Equity commingled funds — 165 — 165 6 150 — 156 Fixed income securities: Government securities — 12 — 12 23 68 — 91 Corporate bonds — 12 — 12 1 14 — 15 Mortgage-backed securities — 14 — 14 — — — — Asset-backed securities and other — 22 — 22 — — — — Fixed income commingled funds — — — — 66 120 — 186 Other: Real estate funds — — 17 17 — — 24 24 Other — — — — 21 107 3 131 Total $ 20 $ 225 $ 17 $ 262 $ 121 $ 459 $ 27 $ 607 U.S. Plans Non-U.S. Plans March 31, 2015 March 31, 2015 (In millions) Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Cash and cash equivalents $ 55 $ 1 $ — $ 56 $ 8 $ — $ — $ 8 Equity securities: Common and preferred stock 18 — — 18 — — — — Equity commingled funds — 138 — 138 7 149 — 156 Fixed income securities: Government securities — 14 — 14 26 53 — 79 Corporate bonds — 14 — 14 — 13 — 13 Mortgage-backed securities — 14 — 14 — — — — Asset-backed securities and other — 26 — 26 — — — — Fixed income commingled funds — — — — 64 127 — 191 Other: Real estate funds — — 18 18 — — 26 26 Other commingled funds — — — — — 13 — 13 Other — — — — 7 115 4 126 Total $ 73 $ 207 $ 18 $ 298 $ 112 $ 470 $ 30 $ 612 Cash and cash equivalents - Cash and cash equivalents include short-term investment funds that maintain daily liquidity and aim to have constant unit values of $1.00 . The funds invest in short-term fixed income securities and other securities with debt-like characteristics emphasizing short-term maturities and high credit quality. Directly held cash and cash equivalents are classified as Level 1 investments. Cash and cash equivalents include money market funds and other commingled funds, which have daily net asset values derived from the underlying securities; these are classified as Level 1 investments. Common and preferred stock - This investment class consists of common and preferred shares issued by U.S. and non-U.S. corporations. Common shares are traded actively on exchanges and price quotes are readily available. Preferred shares may not be actively traded. Holdings of common shares are generally classified as Level 1 investments. Preferred shares are classified as Level 2 investments. Equity commingled funds - Some equity investments are held in commingled funds, which have daily net asset values derived from quoted prices for the underlying securities in active markets; these are classified as Level 1 or Level 2 investments. Fixed income securities - Government securities consist of bonds and debentures issued by central governments or federal agencies; corporate bonds consist of bonds and debentures issued by corporations; mortgage-backed securities consist of debt obligations secured by a mortgage or pool of mortgages; and asset-backed securities primarily consist of debt obligations secured by an asset or pool of assets other than mortgages. Inputs to the valuation methodology include quoted prices for similar assets in active markets, and inputs that are observable for the asset, either directly or indirectly, for substantially the full term of the asset. Multiple prices and price types are obtained from pricing vendors whenever possible, enabling cross-provider price validations. Fixed income securities are generally classified as Level 1 or Level 2 investments. Fixed income commingled funds - Some fixed income investments are held in exchange traded or commingled funds, which have daily net asset values derived from the underlying securities; these are classified as Level 1 or 2 investments. Real estate funds - The value of the real estate funds is reported by the fund manager and is based on a valuation of the underlying properties. Inputs used in the valuation include items such as cost, discounted future cash flows, independent appraisals and market based comparable data. The real estate funds are classified as Level 3 investments. Other commingled funds - The other commingled funds are invested in equities, bonds, commodities, other alternative investments and cash and cash equivalents. These funds are valued based on the weekly net asset values derived from the quoted prices for the underlying securities in active markets and, for alternative investments, based on other valuation techniques. Other commingled funds are classified as Level 1 or Level 2 investments. Other - At March 31, 2016 and 2015, this includes $40 million and $39 million of plan asset value relating to the SPK. In principle, the SPK is organized as a pay-as-you-go system guaranteed by the Norwegian government as it holds no Company-owned assets to back the pension liabilities. The Company pays a pension premium used to fund the plan, which is paid directly to the Norwegian government who establishes an account for each participating employer to keep track of the financial status of the plan, including managing the contributions and the payments. Further, the investment return credited to this account is determined annually by the SPK based on the performance of long-term government bonds. The following table represents a reconciliation of Level 3 plan assets held during the years ended March 31, 2016 and 2015 : U.S. Plans Non-U.S. Plans (In millions) Real Estate Funds Total Real Estate Funds Other Total Balance at March 31, 2014 $ 16 $ 16 $ 7 $ 5 $ 12 Acquisitions — — — — — Unrealized gain on plan assets still held 2 2 1 — 1 Purchases, sales and settlements — — 18 (1 ) 17 Balance at March 31, 2015 $ 18 $ 18 $ 26 $ 4 $ 30 Acquisitions — — — — — Unrealized gain on plan assets still held 1 1 (2 ) (1 ) (3 ) Purchases, sales and settlements (2 ) (2 ) — — — Balance at March 31, 2016 $ 17 $ 17 $ 24 $ 3 $ 27 Multiemployer Plans The Company contributes to a number of multiemployer pension plans under the terms of collective-bargaining agreements that cover union-represented employees in the U.S. In 2016, we also contributed to the Pensjonsordningen for Apoteketaten (“POA”), a mandatory multiemployer pension scheme for our pharmacy employees in Norway, managed by the association of Norwegian Pharmacies. The risks of participating in these multiemployer plans are different from single-employer pension plans in the following aspects: (i) assets contributed to the multiemployer plan by one employer may be used to provide benefits to employees of other participating employers; (ii) if a participating employer stops contributing to the plan, the unfunded obligations of the plan may be borne by the remaining participating employers; and (iii) if the Company chooses to stop participating in some of its multiemployer plans, the Company may be required to pay those plans an amount based on the underfunded status of the plan, referred to as a withdrawal liability. Actions taken by other participating employers may lead to adverse changes in the financial condition of a multiemployer benefit plan and our withdrawal liability and contributions may increase. Contributions and amounts accrued for U.S. Plans were not material for the years ended March 31, 2016, 2015, and 2014. Contributions to the POA for non-U.S. Plans exceeding 5% of total plan contributions were $23 million , $24 million and $5 million in 2016, 2015 and 2014. Based on actuarial calculations, we estimate the funded status for our non-U.S. Plans to be approximately 66% as of March 31, 2016 . No amounts were accrued for liability associated with the POA as we have no intention to withdraw from the plan. Defined Contribution Plans We have a contributory profit sharing investment plan (“PSIP”) for U.S. eligible employees. Eligible employees may contribute to the PSIP up to 75% of their eligible compensation on a pre-tax or post-tax basis not to exceed IRS limits. The Company makes matching contributions in an amount equal to 100% of the employee’s first 3% of pay contributed and 50% for the next 2% of pay contributed. The Company also may make an additional annual matching contribution for each plan year to enable participants to receive a full match based on their annual contribution. The Company also contributed to non-U.S. plans that are available in certain countries. Contribution expenses for the PSIP and non-U.S. plans were $99 million , $103 million and $83 million for the years ended March 31, 2016 , 2015 , and 2014 . Postretirement Benefits We maintain a number of postretirement benefits, primarily consisting of healthcare and life insurance (“welfare”) benefits, for certain eligible U.S. employees. Eligible employees consist of those who retired before March 31, 1999 and those who retired after March 31, 1999, but were an active employee as of that date, after meeting other age-related criteria. We also provide postretirement benefits for certain U.S. executives. Defined benefit plan obligations are measured as of the Company’s fiscal year-end. The net periodic expense for our postretirement welfare benefits is as follows: Years Ended March 31, (In millions) 2016 2015 2014 Service cost - benefits earned during the year $ 1 $ 1 $ 2 Interest cost on accumulated benefit obligation 4 5 5 Amortization of unrecognized actuarial gain and prior service credit — (4 ) (1 ) Curtailment gain — — (2 ) Net periodic postretirement expense $ 5 $ 2 $ 4 Information regarding the changes in benefit obligations for our postretirement welfare plans is as follows: Years Ended March 31, (In millions) 2016 2015 Benefit obligation at beginning of period $ 118 $ 119 Service cost 1 1 Interest cost 4 5 Plan amendments (16 ) — Actuarial loss 3 5 Benefit payments (11 ) (12 ) Curtailment gain (1 ) — Benefit obligation at end of period $ 98 $ 118 The components of the amount recognized in accumulated other comprehensive income for the Company’s other postretirement benefits at March 31, 2016 and 2015 were net actuarial losses of $4 million and $1 million and net prior service credits of $16 million and $1 million . Other changes in benefit obligations recognized in other comprehensive income were net actuarial losses of $3 million in 2016 and $9 million in 2015 and net prior service credits of $16 million in 2016. We estimate that the amortization of the actuarial loss from stockholders’ equity to other postretirement expense in 2017 will be $1 million . Comparable 2016 amount was a gain of $1 million . Other postretirement benefits are funded as claims are paid. Expected benefit payments for our postretirement welfare benefit plans are as follows: $11 million , $9 million , $9 million , $8 million and $8 million for 2017 to 2021 and $34 million cumulatively for 2022 through 2026 . Expected benefit payments are based on the same assumptions used to measure the benefit obligations and include estimated future employee service. Expected contributions to be made for our postretirement welfare benefit plans are $11 million for 2017 . Weighted-average discount rates used to estimate postretirement welfare benefit expenses were 3.59% , 4.07% and 3.84% for 2016 , 2015 and 2014 . Weighted-average discount rates for the actuarial present value of benefit obligations were 3.68% , 3.61% and 4.08% for 2016 , 2015 and 2014 . Actuarial gain or loss for the postretirement welfare benefit plan is amortized to income or expense over a three -year period. The assumed healthcare cost trends used in measuring the accumulated postretirement benefit obligation were 6.50% and 6.75% for prescription drugs, 7.00 / 6.50% and 7.25 / 6.75% for ages pre- 65 /post- 65 medical and 5.00% for dental in 2016 and 2015 . For 2016 , 2015 and 2014 , a one-percentage-point increase or decrease in the assumed healthcare cost trend rate would not have a material impact on the postretirement benefit obligations. Pursuant to various collective bargaining agreements, we contribute to multiemployer health and welfare plans that cover union-represented employees. Our liability is limited to the contractual dollar obligations set forth by the collective bargaining agreements. Contributions to the plans and amounts accrued were not material for the years ended March 31, 2016 , 2015 , and 2014 .

Hedging Activities

Hedging Activities	12 Months Ended
	Mar. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Hedging Activities	Hedging Activities In the normal course of business, we are exposed to interest rate and foreign exchange rate fluctuations. At times, we limit these risks through the use of derivatives such as interest rate swaps, cross currency swaps and foreign currency forward contracts. In accordance with our policy, derivatives are only used for hedging purposes. We do not use derivatives for trading or speculative purposes. Interest rate risk From time to time, we may enter into interest rate swaps which involve the exchange of floating and fixed-rate interest payments. Our interest rate swaps that were outstanding at March 31, 2014 all matured during the first half of 2015. These contracts were not designated for hedge accounting and, accordingly, changes in the fair value of these swaps were recorded directly in earnings. Amounts recorded to earnings were not material for 2015 and 2014. Foreign currency exchange risk We conduct our business worldwide in U.S. dollars and the functional currencies of our foreign subsidiaries, including Euro, British pound sterling and Canadian dollar. Changes in foreign currency exchange rates could have a material adverse impact on our financial results that are reported in U.S. dollars. We are also exposed to foreign currency exchange rate risk related to our foreign subsidiaries, including intercompany loans denominated in non-functional currencies. We have certain foreign currency exchange rate risk programs that use foreign currency forward contracts and cross currency swaps. These forward contracts and cross currency swaps are generally used to offset the potential income statement effects from intercompany loans denominated in non-functional currencies. These programs reduce but do not entirely eliminate foreign exchange rate risk. Derivatives Designated as Hedges At March 31, 2016 and 2015, we had forward contracts to hedge the U.S. dollar against cash flows denominated in Canadian dollars with total gross notional amounts of $323 million and $399 million , which were designated as cash flow hedges. These contracts will mature between March 2017 and March 2020 . During the fourth quarter of 2016, we entered into cross currency swaps to convert fixed-rate British pound sterling denominated borrowings to fixed-rate U.S. dollar borrowings. For our cross currency swap transactions, we agree with another party to exchange, at specified intervals, one currency for another currency at a fixed exchange rate, generally set at inception, calculated by reference to an agreed upon notional amount. The notional amount of each currency is exchanged at the inception and termination of the currency swap by each party. These cross currency swaps are designed to reduce the income statement effects from fluctuations in foreign exchange rates and have been designated as cash flow hedges. The cross currency swaps mature from February 2018 to March 2019 and have a total gross notional amount of approximately $546 million . For forward contracts and currency swaps that are designated as cash flow hedges, the effective portion of changes in the fair values of hedges is recorded into accumulated other comprehensive income and reclassified into earnings in the same period in which the hedged transaction affects earnings. Changes in fair values representing hedge ineffectiveness are recognized in current earnings. Gain or losses on these hedges recorded in other comprehensive income and earnings were not material in 2016, 2015 and 2014. Derivatives Not Designated as Hedges We also have a number of forward contracts to primarily hedge the Euro against cash flows denominated in British pound sterling and other European currencies. At March 31, 2016 and 2015, the total gross notional amounts of these contracts were $876 million and $1,755 million . These contracts will mature through December 2016 and none of these contracts were designated for hedge accounting. Changes in the fair values for contracts not designated as hedges are recorded directly into earnings and accordingly, net gains of $60 million and net losses of $189 million were recorded within operating expenses in 2016 and 2015. The losses from these contracts are largely offset by changes in the value of the underlying intercompany foreign currency loans. Gains and losses from these contracts were not material in 2014. Information regarding the fair value of derivatives on a gross basis is as follows: Balance Sheet Caption March 31, 2016 March 31, 2015 Fair Value of Derivative U.S. Dollar Notional Fair Value of Derivative U.S. Dollar Notional (In millions) Asset Liability Asset Liability Derivatives designated for hedge accounting Foreign exchange contracts (current) Prepaid expenses and other $ 16 $ — $ 80 $ 14 $ — $ 76 Foreign exchange contracts (non-current) Other Noncurrent Assets 46 — 243 53 — 323 Cross currency swaps (non-current) Other Noncurrent Liabilities — 8 546 — — — Total $ 62 $ 8 $ 67 $ — Derivatives not designated for hedge accounting Foreign exchange contracts (current) Prepaid expenses and other $ 23 $ — $ 680 $ 7 $ — $ 493 Foreign exchange contracts (current) Other accrued liabilities — — 196 — 79 1,262 Total $ 23 $ — $ 7 $ 79 Refer to Financial Note 21, “Fair Value Measurements,” for more information on these recurring fair value measurements.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Mar. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. There is a three-level hierarchy that prioritizes the inputs used in determining fair value by their reliability and preferred use, as follows: Level 1 - Valuations based on quoted prices in active markets for identical assets or liabilities. Level 2 - Valuations based on quoted prices in active markets for similar assets and liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data. Level 3 - Valuations based on inputs that are both significant to the fair value measurement and unobservable. At March 31, 2016 and 2015 , the carrying amounts of cash, certain cash equivalents, restricted cash, marketable securities, receivables, drafts and accounts payable, short-term borrowings and other current liabilities approximated their estimated fair values because of the short maturity of these financial instruments. Our long-term debt is carried at amortized cost. The carrying amounts and estimated fair values of these liabilities were $8.1 billion and $8.6 billion at March 31, 2016 and $9.7 billion and $10.4 billion at March 31, 2015 . The estimated fair value of our long-term debt was determined using quoted market prices in a less active market and other observable inputs from available market information, which are considered to be Level 2 inputs, and may not be representative of actual values that could have been realized or that will be realized in the future. Assets Measured at Fair Value on a Recurring Basis Our financial assets measured at fair value on a recurring basis consist of the following: March 31, 2016 March 31, 2015 (In millions ) Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Cash Equivalents Money market funds (1) $ 2,413 $ — $ — $ 2,413 $ 2,880 $ — $ — $ 2,880 Time deposits (2) — — — — — 94 — 94 Repurchase agreements (2) — — — — 1,243 — — 1,243 Total cash equivalents $ 2,413 $ — $ — $ 2,413 $ 4,123 $ 94 $ — $ 4,217 (1) Gross unrealized gain and losses were not material for the years ended March 31, 2016 and 2015 based on quoted prices of identical investments. (2) The carrying amounts of these cash equivalents approximated their estimated fair values because of their short maturities. Fair values of our marketable securities were determined using quoted prices in active markets for identical assets, which are considered Level 1 inputs under the fair value measurements and disclosure guidance. Fair values for our marketable securities were not material at March 31, 2016 and 2015. Fair values of our forward foreign currency contracts were determined using quoted market prices of similar instruments in an active market and other observable inputs from available market information. Fair values of our foreign currency swaps were determined using quoted foreign currency exchange rates and other observable inputs from available market information. These inputs are considered Level 2 under the fair value measurements and disclosure guidance, and may not be representative of actual values that could have been realized or that will be realized in the future. Refer to Financial Note 20, “Hedging Activities,” for fair value and other information on our foreign currency derivatives including foreign currency forward contracts and swaps. There were no transfers between Level 1, Level 2 or Level 3 of the fair value hierarchy during the years ended March 31, 2016 and 2015 . Assets Measured at Fair Value on a Nonrecurring Basis We measure certain long-lived assets and goodwill at fair value on a nonrecurring basis when they are deemed to be other-than-temporarily impaired. If the cost of an investment exceeds its fair value, we evaluate, among other factors, our intent to hold the investment, general market conditions, the duration and extent to which the fair value is less than cost and the financial outlook for the industry and location. An impairment charge is recorded when the cost of the asset exceeds its fair value and this condition is determined to be other-than-temporary. Fiscal 2015 As discussed in Financial Note 9, “Discontinued Operations,” during the fourth quarter of 2015, we recorded a $241 million pre-tax ( $235 million after-tax) non-cash impairment charge to reduce the carrying value of our Brazilian distribution business to its estimated fair value, less cost to sell. The fair value of this business was determined using income and market valuation approaches. Under the income approach, we used a discounted cash flow (“DCF”) analysis based on the estimated future results. This valuation approach is considered a Level 3 fair value measurement due to the use of significant unobservable inputs related to the timing and amount of future cash flows based on projections of revenues and operating costs and discounting those cash flows to their present value. The key inputs and assumptions of the DCF method are the projected cash flows, the terminal value of the business and the discount rate. Under the market approach, we apply valuation multiples of reasonably similar publicly traded companies to the operating data of the subject business to derive the estimated fair value. This valuation approach is also considered a Level 3 fair value measurement. The key inputs for the market valuation approach were revenues and a selection of market multiples. The ultimate loss from the sale of the business may be higher or lower than our current assessment of the business’ fair value. Fiscal 2014 As discussed in Financial Note 9, “Discontinued Operations,” during 2014, we recorded an $80 million non-cash pre-tax and after-tax impairment charge to reduce the carrying value of our International Technology business to its estimated fair value, less costs to sell. The impairment charge was primarily the result of the terms of the preliminary purchase offers received for this business during 2014. Accordingly, the fair value measurement is classified as Level 3 in the fair value hierarchy.

Lease Obligations

Lease Obligations	12 Months Ended
	Mar. 31, 2016
Leases, Operating [Abstract]
Lease Obligations	Lease Obligations We lease facilities and equipment almost solely under operating leases. At March 31, 2016 , future minimum lease payments required under operating leases that have initial or remaining noncancelable lease terms in excess of one year for years ending March 31 are: (In millions) Noncancelable Operating Leases 2017 $ 363 2018 309 2019 252 2020 209 2021 168 Thereafter 669 Total minimum lease payments (1) $ 1,970 (1) Minimum lease payments have not been reduced by minimum sublease rentals of $45 million due under future noncancelable subleases. Rental expense under operating leases was $433 million , $440 million and $298 million in 2016 , 2015 and 2014 . We recognize rent expense on a straight-line basis over the term of the lease, taking into account, when applicable, lessor incentives for tenant improvements, periods where no rent payment is required and escalations in rent payments over the term of the lease. Deferred rent is recognized for the difference between the rent expense recognized on a straight-line basis and the payments made per the terms of the lease. Remaining terms for facilities leases generally range from one to fourteen years, while remaining terms for equipment leases range from one to eight years. Most real property leases contain renewal options (generally for five -year increments) and provisions requiring us to pay property taxes and operating expenses in excess of base period amounts. Sublease rental income was not material for 2016 , 2015 and 2014 .

Financial Guarantees and Warran

Financial Guarantees and Warranties	12 Months Ended
	Mar. 31, 2016
Financial Guarantees And Warranties [Abstract]
Financial Guarantees And Warranties	Financial Guarantees and Warranties Financial Guarantees We have agreements with certain of our customers’ financial institutions, mainly in Canada and Europe, under which we have guaranteed the repurchase of our customers’ inventory or our customers’ debt in the event these customers are unable to meet their obligations to those financial institutions. For our inventory repurchase agreements, among other requirements, inventories must be in resalable condition and any repurchase would be at a discount. The inventory repurchase agreements mostly relate to certain Canadian customers and generally range from one to two years. Customers’ debt guarantees range from one to twelve years and are primarily provided to facilitate financing for certain customers. The majority of our customers’ debt guarantees are secured by certain assets of the customer. At March 31, 2016 , the maximum amounts of inventory repurchase guarantees and customers’ debt guarantees were $201 million and $139 million , of which $1 million had been accrued. The expirations of these financial guarantees are as follows: $194 million , $8 million , $10 million , $12 million and $12 million from 2017 through 2021 and $104 million thereafter. At March 31, 2016 , our banks and insurance companies have issued $142 million of standby letters of credit and surety bonds, which were issued on our behalf mostly related to our customer contracts and in order to meet the security requirements for statutory licenses and permits, court and fiduciary obligations and our workers’ compensation and automotive liability programs. Additionally, at March 31, 2016 , we have a commitment to contribute up to $4 million to a non-consolidated investment for building and equipment construction. Our software license agreements generally include certain provisions for indemnifying customers against liabilities if our software products infringe a third party’s intellectual property rights. To date, we have not incurred any material costs as a result of such indemnification agreements and have not accrued any liabilities related to such obligations. In conjunction with certain transactions, primarily divestitures, we may provide routine indemnification agreements (such as retention of previously existing environmental, tax and employee liabilities) whose terms vary in duration and often are not explicitly defined. Where appropriate, obligations for such indemnifications are recorded as liabilities. Because the amounts of these indemnification obligations often are not explicitly stated, the overall maximum amount of these commitments cannot be reasonably estimated. Other than obligations recorded as liabilities at the time of divestiture, we have historically not made material payments as a result of these indemnification provisions. Warranties In the normal course of business, we provide certain warranties and indemnification protection for our products and services. For example, we provide warranties that the pharmaceutical and medical-surgical products we distribute are in compliance with the U.S. Food, Drug and Cosmetic Act and other applicable laws and regulations. We have received the same warranties from our suppliers, which customarily are the manufacturers of the products. In addition, we have indemnity obligations to our customers for these products, which have also been provided to us from our suppliers, either through express agreement or by operation of law. We also provide warranties regarding the performance of software and products we sell. Our liability under these warranties is to bring the product into compliance with previously agreed upon specifications. For software products, this may result in additional project costs, which are reflected in our estimates used for the percentage-of-completion method of accounting for software installation services within these contracts. In addition, most of our customers who purchase our software and automation products also purchase annual maintenance agreements. Revenues from these maintenance agreements are recognized on a straight-line basis over the contract period and the cost of servicing product warranties is charged to expense when claims become estimable. Accrued warranty costs were not material to the consolidated balance sheets.

Commitments and Contingent Liab

Commitments and Contingent Liabilities	12 Months Ended
	Mar. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingent Liabilities	Commitments and Contingent Liabilities In addition to commitments and obligations in the ordinary course of business, we are subject to various claims, including claims with customers and vendors, pending and potential legal actions for damages, investigations relating to governmental laws and regulations and other matters arising out of the normal conduct of our business. As described below, many of these proceedings are at preliminary stages and many seek an indeterminate amount of damages. When a loss is considered probable and reasonably estimable, we record a liability in the amount of our best estimate for the ultimate loss. However, the likelihood of a loss with respect to a particular contingency is often difficult to predict and determining a meaningful estimate of the loss or a range of loss may not be practicable based on the information available and the potential effect of future events and decisions by third parties that will determine the ultimate resolution of the contingency. Moreover, it is not uncommon for such matters to be resolved over many years, during which time relevant developments and new information must be reevaluated at least quarterly to determine both the likelihood of potential loss and whether it is possible to reasonably estimate a range of possible loss. When a loss is probable but a reasonable estimate cannot be made, disclosure of the proceeding is provided. Disclosure also is provided when it is reasonably possible that a loss will be incurred or when it is reasonably possible that the amount of a loss will exceed the recorded provision. We review all contingencies at least quarterly to determine whether the likelihood of loss has changed and to assess whether a reasonable estimate of the loss or range of loss can be made. As discussed above, development of a meaningful estimate of loss or a range of potential loss is complex when the outcome is directly dependent on negotiations with or decisions by third parties, such as regulatory agencies, the court system and other interested parties. Such factors bear directly on whether it is possible to reasonably estimate a range of potential loss and boundaries of high and low estimates. We are party to the legal proceedings described below. Unless otherwise stated, we are currently unable to estimate a range of reasonably possible losses for the unresolved proceedings described below. Should any one or a combination of more than one of these proceedings be successful, or should we determine to settle any or a combination of these matters, we may be required to pay substantial sums, become subject to the entry of an injunction or be forced to change the manner in which we operate our business, which could have a material adverse impact on our financial position or results of operations. I. Litigation and Claims On September 7, 2007, McKesson Specialty Arizona Inc. was served with a complaint filed in the New York Supreme Court, New York County by PSKW, LLC, alleging that McKesson Specialty Arizona misappropriated trade secrets and confidential information in launching its LoyaltyScript® program, PSKW, LLC v. McKesson Specialty Arizona Inc., Index No. 602921/07 . PSKW later amended its complaint twice to add additional, but related claims. The trial presentation of evidence has completed. The parties are engaged in post-trial briefing. On April 16, 2013, the Company’s wholly-owned subsidiary, U.S. Oncology, Inc. (“USON”), was served with a third amended qui tam complaint filed in the United States District Court for the Eastern District of New York by two relators, purportedly on behalf of the United States, twenty-one states and the District of Columbia, against USON and five other defendants, alleging that USON solicited and received illegal “kickbacks” from Amgen in violation of the Anti-Kickback Statute, the False Claims Act, and various state false claims statutes, and seeking damages, treble damages, civil penalties, attorneys’ fees and costs of suit, all in unspecified amounts, United States ex rel. Piacentile v. Amgen Inc., et al. , CV 04-3983 (SJ). Previously, the United States declined to intervene in the case as to all allegations and defendants except for Amgen. On February 5, 2013, the United States filed a motion to dismiss the claims pled against Amgen. On September 30, 2013, the court granted the United States’ motion to dismiss. On April 4, 2014, USON filed a motion to dismiss the claims pled against it. The court has not yet ruled on USON’s motion. On May 17, 2013, the Company was served with a complaint filed in the United States District Court for the Northern District of California by True Health Chiropractic Inc., alleging that McKesson sent unsolicited marketing faxes in violation of the Telephone Consumer Protection Act of 1991 (“TCPA”), as amended by the Junk Fax Protection Act of 2005 or JFPA, True Health Chiropractic Inc., et al. v. McKesson Corporation, et al., CV-13-02219 (HG). True Health Chiropractic later amended its complaint, adding McLaughlin Chiropractic Associates as an additional named plaintiff and McKesson Technologies Inc. as a defendant. True Health Chiropractic and McLaughlin Chiropractic Associates purport to represent all persons who were sent marketing faxes that did not contain proper opt-out notices and from whom the Company and McKesson Technologies, Inc. did not obtain prior express permission from June 2009 to the present. In July 2015, True Health Chiropractic and McLaughlin Chiropractic Associates filed a motion for class certification. The court has not yet ruled on True Health Chiropractic and McLaughlin Chiropractic Associates’ motion. In August 2015, McKesson was granted a waiver from the opt-out requirement from the Federal Communications Commission (“FCC”). Whether the FCC has the authority to grant such a waiver is currently on appeal before the United States Circuit Court of Appeals for the District of Columbia Circuit. On May 21, 2014, four hedge funds managed by Magnetar Capital filed a complaint against Celesio Holdings (formerly known as “Dragonfly GmbH & Co KGaA”), a wholly-owned subsidiary of the Company, in a German court in Frankfurt, Germany, alleging that Celesio Holdings violated German takeover law in connection with the Company’s acquisition of Celesio by paying more to some holders of Celesio’s convertible bonds than it paid to the shareholders of Celesio’s stock, Magnetar Capital Master Fund Ltd. et al. v. Dragonfly GmbH & Co KGaA, No. 3- 05 O 44/14 . On December 5, 2014, the court dismissed Magnetar’s lawsuit. Magnetar subsequently appealed that ruling. On January 19, 2016, the Appellate Court reversed the lower court’s ruling and entered judgment against Celesio Holdings. On February 22, 2016, Celesio Holdings filed a notice of appeal. On June 17, 2014, U.S. Oncology Specialty, LP (“USOS”) was served with a fifth amended qui tam complaint filed in July 2008 in the United States District Court for the Eastern District of New York by a relator against USOS, among others, alleging that USOS solicited and received illegal “kickbacks” from Amgen in violation of the Anti-Kickback Statute, the False Claims Act, and various state false claims statutes, and seeking damages, treble damages, civil penalties, attorneys’ fees and costs of suit, all in unspecified amounts, United States ex rel. Hanks v. Amgen, Inc., et al. , CV-08-03096 (SJ). Previously, the United States declined to intervene in the case as to all allegations and defendants except for Amgen. On August 1, 2014, USOS filed a motion to dismiss the claims pled against it and the hearing occurred on October 7, 2014. The court has not yet ruled on USOS’s motion. On January 26, 2016, the Company was served with an amended complaint filed in the Circuit Court of Boone County, West Virginia, by three relators, including the Attorney General of West Virginia, purportedly on behalf of the State of West Virginia, alleging that since 2007, the Company has oversupplied controlled substances to West Virginia and failed to report suspicious orders of controlled substances in violation of the West Virginia Controlled Substances Act, the West Virginia Consumer Credit and Protection Act, as well as common law claims for negligence, public nuisance and unjust enrichment, and seeking injunctive relief, monetary damages and civil penalties, State of West Virginia ex rel. Morrisey v. McKesson Corporation , Civil Action No.: 16-C-1. On February 23, 2016, the Company removed this action to the United States District Court for the Southern District of West Virginia (Civil Action No.: 2:16-cv-01772). On March 21, 2016, the Company filed a motion for judgment on the pleadings. On March 24, 2016, the State of West Virginia filed a motion to remand the matter to state court. The court has not yet ruled on either motion. On January 28, 2016, the Company was served with a qui tam lawsuit, filed in the United States District Court, for the Southern District of Texas by a relator, purportedly on behalf of the United States, 29 states and the District of Columbia, against the Company and two other defendants, alleging that the defendants reported materially inaccurate data to manufacturers, which caused manufacturers to submit inaccurate Average Manufacturer Prices (“AMPs”) to the Centers for Medicare and Medicaid Services from January 1, 2004 to the present, in violation of the False Claims Act and various state false claims statutes, and seeking damages, treble damages, civil penalties, attorneys’ fees, interest and costs of suit, United States ex rel. Green v. AmerisourceBergen, et al. , 4:15-CV-00379. The United States declined to intervene in the case as to all allegations and defendants. On April 18, 2016, the Company, along with the other defendants, filed a joint motion to dismiss the claims pled against them. II. Government Subpoenas and Investigations From time-to-time, the Company receives subpoenas or requests for information from various government agencies. The Company generally responds to such subpoenas and requests in a cooperative, thorough and timely manner. These responses sometimes require time and effort and can result in considerable costs being incurred by the Company. Such subpoenas and requests also can lead to the assertion of claims or the commencement of civil or criminal legal proceedings against the Company and other members of the health care industry, as well as to settlements. For example, in the fourth quarter of 2015, the Company reached an agreement in principle with the Drug Enforcement Administration (“DEA”), Department of Justice (“DOJ”) and various U.S. Attorney’s offices to settle all potential administrative and civil claims relating to investigations about the Company’s suspicious order reporting practices for controlled substances. The global settlement with the DEA and DOJ is subject to the execution of final settlement agreements. Under the terms of the agreement in principle, the Company has agreed to pay the sum of $150 million , implement certain remedial measures and have the following distribution centers’ DEA registrations suspended for the specified products and time periods: Aurora, Colorado: all controlled substances for three years; Livonia, Michigan: all controlled substances for two years; Washington Courthouse, Ohio: all controlled substances for the two -year period following completion of the Livonia suspension; and Lakeland, Florida: hydromorphone products for one year. Throughout the terms of these suspensions, the Company will be permitted to continue to ship controlled substances from its Livonia, Washington Courthouse and Lakeland distribution centers to customers that purchase products under its pharmaceutical prime vendor contract with the Department of Veterans Affairs. The Company expects that the suspensions will not result in a supply disruption to any customer. Customers located in the distribution center service areas described above will receive controlled substances from a different distribution center during the applicable suspension periods. As a result of our agreement in principle, during the fourth quarter of 2015, we recorded a $150 million pre-tax and after-tax charge relating to these claims. III. Environmental Matters Primarily as a result of the operation of the Company’s former chemical businesses, which were fully divested by 1987, the Company is involved in various matters pursuant to environmental laws and regulations. The Company has received claims and demands from governmental agencies relating to investigative and remedial actions purportedly required to address environmental conditions alleged to exist at five sites where it, or entities acquired by it, formerly conducted operations and the Company, by administrative order or otherwise, has agreed to take certain actions at those sites, including soil and groundwater remediation. Based on a determination by the Company’s environmental staff, in consultation with outside environmental specialists and counsel, the current estimate of the Company’s probable loss associated with the remediation costs for these five sites is $8.1 million , net of amounts anticipated from third parties. The $8.1 million is expected to be paid out between April 2016 and March 2046 . The Company’s estimated probable loss for these environmental matters has been entirely accrued for in the accompanying consolidated balance sheets. In addition, the Company has been designated as a Potentially Responsible Party (“PRP”) under the Superfund law for environmental assessment and cleanup costs as the result of its alleged disposal of hazardous substances at 15 sites. With respect to these sites, numerous other PRPs have similarly been designated and while the current state of the law potentially imposes joint and several liability upon PRPs, as a practical matter, costs of these sites are typically shared with other PRPs. At one of these sites, the United States Environmental Protection Agency has selected a preferred remedy with an estimated cost of approximately $1.38 billion . It is not certain at this point in time what proportion of this estimated liability will be borne by the Company or by the numerous other PRPs. Accordingly, the Company’s estimated probable loss at those 15 sites is approximately $26 million , which has been entirely accrued for in the accompanying consolidated balance sheets. However, it is possible that the ultimate costs of these matters may exceed or be less than the reserves. IV. Value Added Tax Assessments We operate in various countries outside the United States which collect value added taxes (“VAT”). The determination of the manner in which a VAT applies to our foreign operations is subject to varying interpretations arising from the complex nature of the tax laws. We have received assessments for VAT which are in various stages of appeal. We disagree with these assessments and believe that we have strong legal arguments to defend our tax positions. Certain VAT assessments relate to years covered by an indemnification agreement. Due to the complex nature of the tax laws, it is not possible to estimate the outcome of these matters. However, based on the currently available information, we believe the ultimate outcome of these matters will not have a material adverse effect on our financial position, cash flows or results of operations. V. Average Wholesale Price (“AWP”) Litigation The Company has a reserve relating to AWP public entity claims, which is reviewed at least quarterly and whenever events or circumstances indicate changes. We recorded $68 million of pre-tax charges relating to changes in the Company’s AWP litigation reserve, including accrued interest, in 2014. All charges were recorded in operating expenses within our Distribution Solutions segment. Cash payments of $105 million were made in 2014. At March 31, 2016 and 2015, the reserve for this matter was not material. VI. Other Matters The Company is involved in various other litigation, governmental proceedings and claims, not described above, that arise in the normal course of business. While it is not possible to determine the ultimate outcome or the duration of such litigation, governmental proceedings or claims, the Company believes, based on current knowledge and the advice of counsel, that such litigation, proceedings and claims will not have a material impact on the Company’s financial position or results of operations.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Mar. 31, 2016
Stockholders' Equity Note [Abstract]
Stockholders' Equity	Stockholders’ Equity Each share of the Company’s outstanding common stock is permitted one vote on proposals presented to stockholders and is entitled to share equally in any dividends declared by the Company’s Board of Directors (the “Board”). In July 2015, the quarterly dividend was raised from $0.24 to $0.28 per common share for dividends declared after such date, until further action by the Board. Dividends were $1.08 per share in 2016 , $0.96 per share in 2015 and $0.92 per share in 2014. The Company anticipates that it will continue to pay quarterly cash dividends in the future. However, the payment and amount of future dividends remain within the discretion of the Board and will depend upon the Company’s future earnings, financial condition, capital requirements and other factors. Share Repurchase Plans Stock repurchases may be made from time-to-time in open market transactions, privately negotiated transactions, through accelerated share repurchase (“ASR”) programs, or by any combination of such methods. The timing of any repurchases and the actual number of shares repurchased will depend on a variety of factors, including our stock price, corporate and regulatory requirements, restrictions under our debt obligations and other market and economic conditions. Information regarding the share repurchase activity over the last three years is as follows: Share Repurchases (1) (In millions, except price per share data) Total Number of Shares Purchased (2) (3) Average Price Paid Per Share Approximate Dollar Value of Shares that May Yet Be Purchased Under the Programs Balance, March 31, 2013 $ 340 Shares repurchased — $ — — Balance, March 31, 2014 $ 340 Shares repurchased 1.5 $ 226.55 (340 ) Balance, March 31, 2015 $ — Shares repurchase plans authorized May 2015 500 October 2015 2,000 Shares repurchased 8.7 $ 173.64 (1,504 ) Balance, March 31, 2016 $ 996 (1) This table does not include shares tendered to satisfy the exercise price in connection with cashless exercises of employee stock options or shares tendered to satisfy tax withholding obligations in connection with employee equity awards. (2) All of the shares purchased were part of the publicly announced programs. (3) The number of shares purchased reflects rounding adjustments. In 2016, our share repurchases were transacted through both open market transactions and an ASR program with a third party financial institution. In 2015, all of our share repurchases were conducted through open market transactions. All share repurchases were funded with cash on hand. In 2016, we repurchased 4.5 million of the Company’s shares for $854 million through open market transactions at an average price per share of $192.27 . In February 2016, we entered into an ASR program with a third party financial institution to repurchase $650 million of the Company’s common stock. The ASR program was completed during the fourth quarter and we repurchased 4.2 million shares at an average price per share of $154.04 . During 2016, we completed the May 2015 share repurchase authorization. At March 31, 2016, $1.0 billion remained available for future authorized repurchases of the Company’s common stock under the October 2015 authorization. In 2016, we retired 115.5 million or $7.8 billion by the Company’s treasury shares previously repurchased. Under the applicable state law, these shares resume the status of authorized and unissued shares upon retirement. In accordance with our accounting policy, we allocate any excess of share repurchase price over par value between additional paid-in capital and retained earnings. Accordingly, our retained earnings and additional paid-in capital were reduced by $6.35 billion and $1.5 billion during 2016. Other Comprehensive Income (Loss) Information regarding other comprehensive income (loss) including noncontrolling interests and redeemable noncontrolling interests, net of tax, by component is as follows: Years Ended March 31, (In millions) 2016 2015 2014 Foreign currency translation adjustments (1) Foreign currency translation adjustments arising during period, net of income tax expense (benefit) of ($23), nil and nil (2) (3) $ 113 $ (1,845 ) $ 9 Reclassified to income statement, net of income tax expense of nil, nil and 24 (4) — (10 ) 44 113 (1,855 ) 53 Unrealized gains (losses) on cash flow hedges Unrealized gains (losses) on cash flow hedges arising during period, net of income tax benefit of nil, nil and nil 6 (13 ) (6 ) Reclassified to income statement, net of income tax expense of nil, nil and nil 3 3 — 9 (10 ) (6 ) Changes in retirement-related benefit plans Net actuarial gain (loss) and prior service credit (cost) arising during period, net of income tax expense (benefit) of $13, ($66) and $16 (5) 23 (140 ) 17 Amortization of actuarial loss, prior service cost and transition obligation, net of income tax expense of $18, $6 and $12 (6) 30 11 22 Foreign currency translation adjustments and other, net of income tax expense of nil, nil and nil (3 ) 4 (4 ) Reclassified to income statement, net of income tax expense of nil, nil, and $1 — 1 1 50 (124 ) 36 Other Comprehensive Income (Loss), net of tax $ 172 $ (1,989 ) $ 83 (1) Foreign currency translation adjustments result from the conversion of non-U.S. dollar financial statements of our foreign subsidiaries into the Company’s reporting currency, U.S. dollars, and were primarily related to our foreign subsidiary, Celesio, in 2016 and 2015. (2) The 2016 net foreign currency translation gains of $113 million were primarily due to the recovery of the Euro against the U.S. dollar, partly offset by the weakening of the Canadian dollar and British pound sterling against the U.S. dollar during the period between April 1, 2015 and March 31, 2016. The 2015 foreign currency translation losses of $1,855 million were primarily due to the weakening of the Euro against U.S. dollar during the period between April 1, 2014 and March 31, 2015. (3) 2016 includes net foreign currency translation gains of $16 million and 2015 includes net foreign currency translations losses of $267 million attributable to noncontrolling and redeemable noncontrolling interests. (4) These net foreign currency losses were reclassified from accumulated other comprehensive income (loss) to discontinued operations within our consolidated statement of operations due to the sale of certain businesses. (5) The net gains of $4 million and net losses of $12 million attributable to noncontrolling and redeemable noncontrolling interests in 2016 and 2015. (6) Pre-tax amount was reclassified into cost of sales and operating expenses in the consolidated statements of operations. The related tax expense was reclassified into income tax expense in the consolidated statements of operations. Accumulated Other Comprehensive Income (Loss) Information regarding changes in our accumulated other comprehensive income (loss) by component are as follows: (In millions) Foreign Currency Translation Adjustments, Net of Tax Unrealized Losses on Cash Flow Hedges, Net of Tax Unrealized Net Gains (Losses) and Other Components of Benefit Plans, Net of Tax Total Accumulated Other Comprehensive Income (Loss) Balance at March 31, 2014 $ 168 $ (11 ) $ (160 ) $ (3 ) Other comprehensive income (loss) before reclassifications (1,845 ) (13 ) (136 ) (1,994 ) Amounts reclassified to earnings (10 ) 3 12 5 Other comprehensive income (loss) $ (1,855 ) $ (10 ) $ (124 ) $ (1,989 ) Less: amounts attributable to noncontrolling and redeemable interests (267 ) — (12 ) (279 ) Other comprehensive income (loss) attributable to McKesson $ (1,588 ) $ (10 ) $ (112 ) $ (1,710 ) Balance at March 31, 2015 $ (1,420 ) $ (21 ) $ (272 ) $ (1,713 ) Other comprehensive income (loss) before reclassifications 113 6 23 142 Amounts reclassified to earnings and other — 3 27 30 Other comprehensive income (loss) $ 113 $ 9 $ 50 $ 172 Less: amounts attributable to noncontrolling and redeemable interests 16 — 4 20 Other comprehensive income (loss) attributable to McKesson $ 97 $ 9 $ 46 $ 152 Balance at March 31, 2016 $ (1,323 ) $ (12 ) $ (226 ) $ (1,561 )

Related Party Balances and Tran

Related Party Balances and Transactions	12 Months Ended
	Mar. 31, 2016
Related Party Transactions [Abstract]
Related Party Balances and Transactions	Related Party Balances and Transactions Celesio has investments in pharmacies located across Europe that are accounted for under the equity-method. Celesio maintains distribution arrangements with these pharmacies for the sale of related goods and services under which revenues of $112 million and $114 million are included in our consolidated statement of operations in 2016 and 2015, and receivables of $8 million and $9 million are included in our consolidated balance sheet for the year ended March 31, 2016 and 2015.

Segments of Business

Segments of Business	12 Months Ended
	Mar. 31, 2016
Segment Reporting [Abstract]
Segments of Business	Segments of Business We report our operations in two operating segments: McKesson Distribution Solutions and McKesson Technology Solutions. The factors for determining the reportable segments included the manner in which management evaluates the performance of the Company combined with the nature of the individual business activities. We evaluate the performance of our operating segments on a number of measures, including operating profit before interest expense, income taxes and results from discontinued operations. The Distribution Solutions segment distributes branded and generic pharmaceutical drugs and other healthcare-related products worldwide and provides medical-surgical supply distribution, equipment, logistics and other services to healthcare providers within the United States. This segment provides practice management, technology, clinical support and business solutions to community-based oncology and other specialty practices. It also provides specialty pharmaceutical solutions for pharmaceutical manufacturers including offering multiple distribution channels and clinical trial access to our network of oncology physicians. Additionally, this segment operates retail pharmacies in Europe and supports independent pharmacy networks within North America. It also sells financial, operational and clinical solutions to pharmacies (retail, hospital, alternate site) and provides consulting, outsourcing and other services. The McKesson Technology Solutions segment delivers enterprise-wide clinical, patient care, financial, supply chain, strategic management software solutions, as well as connectivity, outsourcing and other services, including remote hosting and managed services, to healthcare organizations. Corporate includes expenses associated with Corporate functions and projects and the results of certain investments. Corporate expenses are allocated to the operating segments to the extent that these items can be directly attributable to the segment. Financial information relating to our reportable operating segments and reconciliations to the consolidated totals is as follows: Years Ended March 31, (In millions) 2016 2015 2014 Revenues Distribution Solutions (1) North America pharmaceutical distribution and services $ 158,469 $ 143,711 $ 123,929 International pharmaceutical distribution and services 23,497 26,358 4,485 Medical-Surgical distribution and services 6,033 5,907 5,648 Total Distribution Solutions 187,999 175,976 134,062 Technology Solutions - products and services 2,885 3,069 3,330 Total Revenues $ 190,884 $ 179,045 $ 137,392 Operating profit Distribution Solutions (2) (4) $ 3,553 $ 3,047 $ 2,472 Technology Solutions (3) (4) 519 438 448 Total 4,072 3,485 2,920 Corporate Expenses, Net (4) (469 ) (454 ) (449 ) Interest Expense (353 ) (374 ) (300 ) Income From Continuing Operations Before Income Taxes $ 3,250 $ 2,657 $ 2,171 Depreciation and amortization (5) Distribution Solutions $ 669 $ 750 $ 446 Technology Solutions 107 156 169 Corporate 109 111 120 Total $ 885 $ 1,017 $ 735 Expenditures for long-lived assets (6) Distribution Solutions $ 306 $ 301 $ 179 Technology Solutions 15 27 47 Corporate 167 48 52 Total $ 488 $ 376 $ 278 Revenues, net by geographic area (7) United States $ 158,255 $ 142,810 $ 122,426 Foreign 32,629 36,235 14,966 Total $ 190,884 $ 179,045 $ 137,392 (1) Revenues derived from services represent less than 2% of this segment’s total revenues. (2) Distribution Solutions operating profit for the year ended March 31, 2016, 2015, and 2014 include $244 million , $337 million , and $311 million in pre-tax charges related to our last-in, first-out (“LIFO”) method of accounting for inventories. LIFO expense was less in 2016 primarily due to lower net price increases. For the year ended March 31, 2016 includes $76 million of net cash proceeds representing our share of net settlements of antitrust class action lawsuits as well as a pre-tax gain of $52 million recognized from the sale of our ZEE Medical business. (3) Technology Solutions operating profit for the year ended March 31, 2016 includes a pre-tax gain of $51 million recognized from the sale of our nurse triage business, and for year ended March 31, 2015 includes a non-cash pre-tax charge of $34 million related to the retained workforce business within our International Technology business. (4) During the fourth quarter of 2016, the Company approved the Cost Alignment Plan to reduce its operating expenses and recorded pre-tax restructuring charges of $229 million . Pre-tax charges were recorded as follows: $161 million , $51 million and $17 million within our Distribution Solutions segment, Technology Solutions segment and Corporate. (5) Amounts primarily include amortization of acquired intangible assets purchased in connection with business acquisitions, capitalized software held for sale and capitalized software for internal use. (6) Long-lived assets consist of property, plant and equipment. (7) Net revenues were attributed to geographic areas based on the customers’ shipment locations. Segment assets and property, plant and equipment, net by geographic areas were as follows: March 31, (In millions) 2016 2015 Segment assets Distribution Solutions $ 47,088 $ 43,982 Technology Solutions 3,072 3,281 Total 50,160 47,263 Corporate Cash and cash equivalents 4,048 5,341 Other 2,355 1,266 Total $ 56,563 $ 53,870 Property, plant and equipment, net United States $ 1,500 $ 1,273 Foreign 778 772 Total $ 2,278 $ 2,045

Quarterly Financial Information

Quarterly Financial Information (Unaudited)	12 Months Ended
	Mar. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Information (Unaudited)	Quarterly Financial Information (Unaudited) The quarterly results of operations are not necessarily indicative of the results that may be expected for the entire year. Selected quarterly financial information for the last two years is as follows: (In millions, except per share amounts) First Quarter Second Quarter Third Quarter Fourth Quarter Fiscal 2016 Revenues $ 47,546 $ 48,761 $ 47,899 $ 46,678 Gross profit (1) (2) (3) 2,848 2,844 2,872 2,852 Income after income taxes: Continuing operations (1) (3) (4) $ 599 $ 636 $ 642 $ 465 Discontinued operations (10 ) (6 ) 5 (21 ) Net income $ 589 $ 630 $ 647 $ 444 Net income attributable to McKesson $ 576 $ 617 $ 634 $ 431 Earnings (loss) per common share attributable to McKesson (5) Diluted Continuing operations $ 2.50 $ 2.65 $ 2.71 $ 1.97 Discontinued operations (0.05 ) (0.02 ) 0.02 (0.09 ) Total $ 2.45 $ 2.63 $ 2.73 $ 1.88 Basic Continuing operations $ 2.53 $ 2.68 $ 2.74 $ 1.99 Discontinued operations (0.04 ) (0.02 ) 0.02 (0.09 ) Total $ 2.49 $ 2.66 $ 2.76 $ 1.90 (1) Gross profit for the first, second, third and fourth quarters of 2016 included pre-tax charges related to our last-in-first-out (“LIFO”) method of accounting for inventories of $91 million , $91 million , $33 million and $29 million . (2) Gross profit for the first and third quarters of 2016 included $59 million and $17 million of cash proceeds representing our share of net settlements of antitrust class action lawsuits against drug manufacturers. (3) Financial results for the fourth quarter of 2016 include pre-tax restructuring charges of $229 million within our continuing operations. Charges were recorded as follows: $26 million in cost of sales and $203 million in operating expenses. (4) Financial results for the first quarter of 2016 include an after-tax gain of $38 million from the sale of our nurse triage business, and for the second quarter of 2016 include an after-tax gain of $29 million from the sale of ZEE Medical business. (5) Certain computations may reflect rounding adjustments. (In millions, except per share amounts) First Quarter Second Quarter Third Quarter Fourth Quarter Fiscal 2015 Revenues $ 43,476 $ 44,160 $ 46,484 $ 44,925 Gross profit (1) 2,732 2,864 2,898 2,917 Income after income taxes Continuing operations (1) (2) $ 419 $ 491 $ 521 $ 411 Discontinued operations (3) (8 ) (14 ) (10 ) (267 ) Net income $ 411 $ 477 $ 511 $ 144 Net income attributable to McKesson $ 403 $ 469 $ 472 $ 132 Earnings per common share attributable to McKesson (4) Diluted Continued operations $ 1.76 $ 2.05 $ 2.04 $ 1.69 Discontinued operations (0.04 ) (0.06 ) (0.04 ) (1.13 ) Total $ 1.72 $ 1.99 $ 2.00 $ 0.56 Basic Continuing operations $ 1.79 $ 2.08 $ 2.07 $ 1.72 Discontinued operations (0.04 ) (0.06 ) (0.04 ) (1.15 ) Total $ 1.75 $ 2.02 $ 2.03 $ 0.57 (1) Gross profit for the first, second, third and fourth quarters of 2015 included pre-tax charges related to our LIFO method of accounting for inventories of $98 million , $94 million , $95 million and $50 million . (2) Financial results for the fourth quarter of 2015 included a non-cash after-tax charge of $150 million related to the settlement of controlled substance distribution claims. (3) Discontinued operations for the fourth quarter of 2015 included $235 million non-cash after-tax impairment charges related to our Brazilian pharmaceutical distribution business. (4) Certain computations may reflect rounding adjustments.

SUPPLEMENTARY CONSOLIDATED FINA

SUPPLEMENTARY CONSOLIDATED FINANCIAL STATEMENT SCHEDULE VALUATION AND QUALIFYING ACCOUNTS	12 Months Ended
	Mar. 31, 2016
Valuation and Qualifying Accounts [Abstract]
SUPPLEMENTARY CONSOLIDATED FINANCIAL STATEMENT SCHEDULE VALUATION AND QUALIFYING ACCOUNTS	SUPPLEMENTARY CONSOLIDATED FINANCIAL STATEMENT SCHEDULE VALUATION AND QUALIFYING ACCOUNTS For the Years Ended March 31, 2016 , 2015 and 2014 (In millions) Additions Description Balance at Beginning of Year Charged to Costs and Expenses Charged to Other Accounts (3) Deductions From Allowance Accounts (1) Balance at End of Year (2) Year Ended March 31, 2016 Allowances for doubtful accounts $ 141 $ 113 $ 2 $ (44 ) $ 212 Other allowances 33 — (3 ) 11 41 $ 174 $ 113 $ (1 ) $ (33 ) $ 253 Year Ended March 31, 2015 Allowances for doubtful accounts $ 112 $ 67 $ — $ (38 ) $ 141 Other allowances 22 8 — 3 33 $ 134 $ 75 $ — $ (35 ) $ 174 Year Ended March 31, 2014 Allowances for doubtful accounts $ 121 $ 36 $ (11 ) $ (34 ) $ 112 Other allowances 15 — 10 (3 ) 22 $ 136 $ 36 $ (1 ) $ (37 ) $ 134 2016 2015 2014 (1) Deductions: Written off $ (33 ) $ (34 ) $ (39 ) Credited to other accounts — (1 ) 2 Total $ (33 ) $ (35 ) $ (37 ) (2) Amounts shown as deductions from current and non-current receivables $ 253 $ 174 $ 134 (3) Primarily represents reclassifications from other balance sheet accounts.

Significant Accounting Polici38

Significant Accounting Policies (Policies)	12 Months Ended
	Mar. 31, 2016
Accounting Policies [Abstract]
Nature of Operations	Nature of Operations : McKesson Corporation (“McKesson,” the “Company,” the “Registrant” or “we” and other similar pronouns) delivers a comprehensive offering of pharmaceuticals and medical supplies and provides services to help our customers improve the efficiency and effectiveness of their healthcare operations. We manage our business through two operating segments, McKesson Distribution Solutions and McKesson Technology Solutions, as further described in Financial Note 27, “Segments of Business.”
Basis of Presentation	Basis of Presentation: The consolidated financial statements and accompanying notes are prepared in accordance with U. S. generally accepted accounting principles (“GAAP”). The consolidated financial statements of McKesson include the financial statements of all wholly-owned subsidiaries and majority-owned or controlled companies. For those consolidated subsidiaries where our ownership is less than 100% , the portion of the net income or loss allocable to the noncontrolling interests is reported as “Net Income Attributable to Noncontrolling Interests” on the consolidated statements of operations. All significant intercompany balances and transactions have been eliminated in consolidation. We consider ourselves to control an entity if we are the majority owner of and have voting control over such entity. We also assess control through means other than voting rights (“variable interest entities” or “VIEs”) and determine which business entity is the primary beneficiary of the VIE. We consolidate VIEs when it is determined that we are the primary beneficiary of the VIE. Investments in business entities in which we do not have control, but have the ability to exercise significant influence over operating and financial policies, are accounted for using the equity method and our proportionate share of income or loss is recorded in other income, net. Equity investments in non-publicly traded entities are primarily accounted for using the cost method. Intercompany transactions and balances have been eliminated.
Fiscal Period	Fiscal Period: The Company’s fiscal year begins on April 1 and ends on March 31. Unless otherwise noted, all references to a particular year shall mean the Company’s fiscal year.
Reclassifications	Reclassifications : Certain prior year amounts have been reclassified to conform to the current year presentation.
Use of Estimates	Use of Estimates : The preparation of financial statements in conformity with U.S. GAAP requires that we make estimates and assumptions that affect the reported amounts in the consolidated financial statements and accompanying notes. Actual amounts could differ from those estimated amounts.
Cash and Cash Equivalents	Cash and Cash Equivalents : All highly liquid debt and money market instruments purchased with original maturity of three months or less at the date of acquisition are included in cash and cash equivalents. Cash equivalents, which are available-for-sale, are carried at fair value. Cash equivalents are primarily invested in AAA rated prime and U.S. government money market funds denominated in U.S. dollars, AAA rated prime money market funds denominated in Euros, overnight repurchase agreements collateralized by U.S. government securities, Canadian government securities and/or securities that are guaranteed or sponsored by the U.S. government and an AAA rated prime money market fund denominated in British pound sterling. The remaining cash and cash equivalents are deposited with several financial institutions. Deposits may exceed the amounts insured by the Federal Deposit Insurance Corporation in the U.S. and similar deposit insurance programs in other jurisdictions. We mitigate the risk of our short-term investment portfolio by depositing funds with reputable financial institutions and monitoring risk profiles and investment strategies of money market funds.
Restricted Cash	Restricted Cash : Cash that is subject to legal restrictions or is unavailable for general operating purposes is classified as restricted cash and is included within “Prepaid expenses and other” and “Other Noncurrent Assets” in the consolidated balance sheets.
Marketable Securities Available-for-Sale	Marketable Securities Available-for-Sale : We carry our marketable securities, which are available-for-sale, at fair value and they are included in prepaid expenses and other in the consolidated balance sheets. The unrealized gains and losses, net of the related tax effect, computed in marking these securities to market have been reported within stockholders’ equity. At March 31, 2016 and 2015 , marketable securities were not material. In determining whether an other-than-temporary decline in market value has occurred, we consider the duration that, and extent to which, the fair value of the investment is below its cost, the financial condition and future prospects of the issuer or underlying collateral of a security, and our intent and ability to retain the security in order to allow for an anticipated recovery in fair value. Other-than-temporary declines in fair value from amortized cost for available-for-sale equity securities that we intend to sell or would more likely than not be required to sell before the expected recovery of the amortized cost basis are charged to other income, net, in the period in which the loss occurs.
Concentrations of Credit Risk and Receivables	Concentrations of Credit Risk and Receivables: Our trade receivables are subject to a concentration of credit risk with customers primarily in our Distribution Solutions segment. During 2016 , sales to our ten largest customers, including group purchasing organizations (“GPOs”) accounted for approximately 52.4% of our total consolidated revenues. Sales to our largest customer, CVS Health (“CVS”), accounted for approximately 20.3% of our total consolidated revenues. At March 31, 2016 , trade accounts receivable from our ten largest customers were approximately 32% of total trade accounts receivable. Accounts receivable from CVS were approximately 18% of total trade accounts receivable. As a result, our sales and credit concentration is significant. We also have agreements with GPOs, each of which functions as a purchasing agent on behalf of member hospitals, pharmacies and other healthcare providers, as well as with government entities and agencies. The accounts receivables balances are with individual members of the GPOs, and therefore no significant concentration of credit risk exists. A default in payment, a material reduction in purchases from these or any other large customers, or the loss of a large customer or customer groups could have a material adverse impact on our financial condition, results of operations and liquidity. In addition, trade receivables are subject to a concentration of credit risk with customers in the institutional, retail and healthcare provider sectors, which can be affected by a downturn in the economy and changes in reimbursement policies. This credit risk is mitigated by the size and diversity of the customer base as well as its geographic dispersion. We estimate the receivables for which we do not expect full collection based on historical collection rates and ongoing evaluations of the creditworthiness of our customers. An allowance is recorded in our consolidated financial statements for these amounts.
Financing Receivables	Financing Receivables: We assess and monitor credit risk associated with financing receivables, namely lease and notes receivables, through regular review of our collection experience in determining our allowance for loan losses. On an ongoing basis, we also evaluate credit quality of our financing receivables utilizing aging of receivables and write-offs, as well as considering existing economic conditions, to determine if an allowance is necessary. Financing receivables are derecognized if legal title to them has been transferred and all related risks and rewards incidental to ownership have passed to the buyer.
Inventories	Inventories: We report inventories at the lower of cost or market (“LCM”). Inventories for our Distribution Solutions segment consist of merchandise held for resale. For our Distribution Solutions segment, the majority of the cost of domestic inventories is determined using the last-in, first-out (“LIFO”) method. The majority of the cost of inventories held in foreign locations is based on weighted average purchase prices using the first-in, first-out method (“FIFO”). Technology Solutions segment inventories consist of computer hardware with cost generally determined by the standard cost method, which approximates average cost. Rebates, cash discounts, and other incentives received from vendors are recognized within cost of sales upon the sale of the related inventory. The LIFO method was used to value approximately 74% and 73% of our inventories at March 31, 2016 and 2015 . If we had used the FIFO method of inventory valuation, which approximates current replacement costs, inventories would have been approximately $1,012 million and $768 million higher than the amounts reported at March 31, 2016 and 2015 , respectively. These amounts are equivalent to our LIFO reserves. Our LIFO valuation amount includes both pharmaceutical and non-pharmaceutical products. In 2016 , 2015 and 2014 , we recognized LIFO related expenses of $244 million , $337 million and $311 million in cost of sales within our consolidated statements of operations. A LIFO expense is recognized when the net effect of price increases on pharmaceutical and non-pharmaceutical products held in inventory exceeds the impact of price declines, including the effect of branded pharmaceutical products that have lost market exclusivity. A LIFO credit is recognized when the net effect of price declines exceeds the impact of price increases on pharmaceutical and non-pharmaceutical products held in inventory. We believe that the average inventory costing method provides a reasonable estimation of the current cost of replacing inventory (i.e., “market”). As such, our LIFO inventory is valued at the lower of LIFO or market.
Shipping and Handling Costs	Shipping and Handling Costs: We include costs to pack and deliver inventory to our customers in selling, distribution and administrative expenses.
Property, Plant and Equipment	Property, Plant and Equipment: We state our property, plant and equipment (“PPE”) at cost and depreciate them under the straight-line method at rates designed to distribute the cost of PPE over estimated service lives ranging from one to thirty years. When certain events or changes in operating conditions occur, an impairment assessment may be performed on the recoverability of the carrying amounts.
Goodwill	Goodwill: Goodwill is tested for impairment on an annual basis in the fourth quarter or more frequently if indicators for potential impairment exist. Impairment testing is conducted at the reporting unit level, which is generally defined as a component, one level below our Distribution Solutions and Technology Solutions operating segments, for which discrete financial information is available and segment management regularly reviews the operating results of that unit. The first step in goodwill testing requires us to compare the estimated fair value of a reporting unit to its carrying value. This step may be performed utilizing either a qualitative or quantitative assessment. If the carrying value of the reporting unit is lower than its estimated fair value, no further evaluation is necessary. If the carrying value of the reporting unit is higher than its estimated fair value, the second step must be performed to measure the amount of impairment loss. Under the second step, the implied fair value of goodwill is calculated in a hypothetical analysis by subtracting the fair value of all assets and liabilities of the reporting unit, including any unrecognized intangible assets, from the fair value of the reporting unit calculated in the first step of the impairment test. If the carrying value of goodwill for the reporting unit exceeds the implied fair value of goodwill, an impairment charge is recorded for that excess. To estimate the fair value of our reporting units, we use a combination of the market approach and the income approach. Under the market approach, we estimate fair value by comparing the business to similar businesses or guideline companies whose securities are actively traded in public markets. Under the income approach, we use a discounted cash flow model in which cash flows anticipated over several periods, plus a terminal value at the end of that time horizon, are discounted to their present value using an appropriate expected rate of return. The discount rate used for cash flows reflects capital market conditions and the specific risks associated with the business. In addition, we compare the aggregate of the reporting units’ fair value to the Company’s market capitalization as a further corroboration of the fair values. The testing requires a complex series of assumptions and judgment by management in projecting future operating results, selecting guideline companies for comparisons and assessing risks. The use of alternative assumptions and estimates could affect the fair values and change the impairment determinations.
Intangible Assets	Intangible Assets: Currently all of our intangible assets are subject to amortization and are amortized based on the pattern of their economic consumption or on a straight-line basis over their estimated useful lives, ranging from one to thirty-eight years. We review intangible assets for impairment whenever events or changes in circumstances indicate that the carrying value of the assets may not be recoverable. Determination of recoverability is based on the lowest level of identifiable estimated future undiscounted cash flows resulting from use of the asset and its eventual disposition. Measurement of any impairment loss is based on the excess of the carrying value of the asset over its fair market value.
Capitalized Software Held for Sale	Capitalized Software Held for Sale: Development costs for software held for sale, which primarily pertain to our Technology Solutions segment, are capitalized once a project has reached the point of technological feasibility. Completed projects are amortized after reaching the point of general availability using the straight-line method based on an estimated useful life of approximately three years. At each balance sheet date, or earlier if an indicator of an impairment exists, we evaluate the recoverability of unamortized capitalized software costs based on estimated future undiscounted revenues net of estimated related costs over the remaining amortization period.
Capitalized Software Held for Internal Use	Capitalized Software Held for Internal Use: We capitalize costs of software held for internal use during the application development stage of a project and amortize those costs over their estimated useful lives ranging from one to ten years.
Insurance Programs	Insurance Programs: Under our insurance programs, we seek to obtain coverage for catastrophic exposures as well as those risks required to be insured by law or contract. It is our policy to retain a significant portion of certain losses primarily related to workers’ compensation and comprehensive general, product and vehicle liability. Provisions for losses expected under these programs are recorded based upon our estimate of the aggregate liability for claims incurred as well as for claims incurred but not yet reported. Such estimates utilize certain actuarial assumptions followed in the insurance industry.
Revenue Recognition	Revenue Recognition: Distribution Solutions Revenues for our Distribution Solutions segment are recognized when persuasive evidence of an arrangement exists, product is delivered and title passes to the customer or when services have been rendered and there are no further obligations to the customer, the price is fixed or determinable, and collection of the amounts are reasonably assured. Revenues for our Distribution Solutions segment include large volume sales of pharmaceuticals primarily to a limited number of large customers who warehouse their own products. We order bulk product from the manufacturer, receive and process the product primarily through our central distribution facility and deliver the bulk product (generally in the same form as received from the manufacturer) directly to our customers’ warehouses. We also record revenues for direct store deliveries of shipments from the manufacturer to our customers. We assume the primary liability to the manufacturer for these products. Revenues are recorded gross when we are the primary party obligated in the transaction, take title to and possession of the inventory, are subject to inventory risk, have latitude in establishing prices, assume the risk of loss for collection from customers as well as delivery or return of the product, are responsible for fulfillment and other customer service requirements, or the transactions have several but not all of these indicators. Revenues are recorded net of sales returns, allowances, rebates and other incentives. Our sales return policy generally allows customers to return products only if they can be resold for value or returned to suppliers for credit. Sales returns are accrued based on estimates at the time of sale to the customer. Sales returns from customers were approximately $3.1 billion in 2016 , $2.7 billion in 2015 and $1.9 billion in 2014 . Taxes collected from customers and remitted to governmental authorities are presented on a net basis; that is, they are excluded from revenues. Our Distribution Solutions segment also engages in multiple-element arrangements, which may contain a combination of various products and services. Revenue from a multiple-element arrangement is allocated to the separate elements based on their relative selling price and recognized in accordance with the revenue recognition criteria applicable to each element. Relative selling price is determined based on vendor-specific objective evidence (“VSOE”) of selling price, if available, third-party evidence (“TPE”), if VSOE of selling price is not available, or estimated selling price (“ESP”), if neither VSOE of selling price nor TPE is available. Technology Solutions Revenues for our Technology Solutions segment are generated primarily by licensing software and software systems (consisting of software, hardware and maintenance support), providing software as a service (“Saas”) or SaaS-based solutions and providing claims processing, outsourcing and professional services. Revenue for this segment is recognized as follows: Software systems are marketed under information systems agreements as well as service agreements. Perpetual software arrangements are recognized at the time of delivery or under the percentage-of-completion method if the arrangements require significant production, modification or customization of the software. Contracts accounted for under the percentage-of-completion method are generally measured based on the ratio of labor hours incurred to date to total estimated labor hours to be incurred. Changes in estimates to complete and revisions in overall profit estimates on these contracts are charged to earnings in the period in which they are determined. We accrue for contract losses if and when the current estimate of total contract costs exceeds total contract revenue. Revenue from time-based software license agreements is recognized ratably over the term of the agreement. Software implementation fees are recognized as the work is performed or under the percentage-of-completion method. Maintenance and support agreements are marketed under annual or multi-year agreements and are recognized ratably over the period covered by the agreements. Hardware revenues are generally recognized upon delivery. SaaS-based subscription, content and transaction processing fees are generally marketed under annual and multi-year agreements and are recognized ratably over the contracted terms beginning on the service start date for fixed fee arrangements and recognized as transactions are performed beginning on the service start date for per-transaction fee arrangements. Remote processing service fees are recognized monthly as the service is performed. Outsourcing service revenues are recognized as the service is performed. We also offer certain products on an application service provider basis, making our software functionality available on a remote hosting basis from our data centers. The data centers provide system and administrative support, as well as hosting services. Revenue on products sold on an application service provider basis is recognized on a monthly basis over the term of the contract beginning on the service start date of products hosted. This segment engages in multiple-element arrangements, which may contain any combination of software, hardware, implementation, SaaS-based offerings, consulting services or maintenance services. For multiple-element arrangements that do not include software, revenue is allocated to the separate elements based on their relative selling price and recognized in accordance with the revenue recognition criteria applicable to each element. Relative selling price is determined based on VSOE of selling price if available, TPE, if VSOE of selling price is not available, or ESP if neither VSOE of selling price nor TPE is available. For multiple-element arrangements accounted for in accordance with specific software accounting guidance when some elements are delivered prior to others in an arrangement and VSOE of fair value exists for the undelivered elements, revenue for the delivered elements is recognized upon delivery of such items. The segment establishes VSOE for hardware and implementation and consulting services based on the price charged when sold separately, and for maintenance services, based on renewal rates offered to customers. Revenue for the software element is recognized under the residual method only when fair value has been established for all of the undelivered elements in an arrangement. If fair value cannot be established for any undelivered element, all of the arrangement’s revenue is deferred until the delivery of the last element or until the fair value of the undelivered element is determinable. For multiple-element arrangements with both software elements and nonsoftware elements, arrangement consideration is allocated between the software elements as a whole and nonsoftware elements. The segment then further allocates consideration to the individual elements within the software group, and revenue is recognized for all elements under the applicable accounting guidance and our policies described above.
Supplier Incentives	Supplier Incentives: Fees for service and other incentives received from suppliers, relating to the purchase or distribution of inventory, are generally reported as a reduction to cost of sales. We consider these fees and other incentives to represent product discounts and as a result, the amounts are recognized within cost of sales upon the sale of the related inventory.
Supplier Reserves	Supplier Reserves: We establish reserves against amounts due from suppliers relating to various fees for services and price and rebate incentives, including deductions taken against payments otherwise due to them. These reserve estimates are established based on judgment after considering the status of current outstanding claims, historical experience with the suppliers, the specific incentive programs and any other pertinent information available. We evaluate the amounts due from suppliers on a continual basis and adjust the reserve estimates when appropriate based on changes in factual circumstances. All adjustments to supplier reserves are included in cost of sales. The ultimate outcome of any outstanding claims may be different than our estimate.
Income Taxes	Income Taxes: We account for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements. Under this method, deferred tax assets and liabilities are determined based on the difference between the financial statements and the tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Tax benefits from uncertain tax positions are recognized when it is more likely than not that the position will be sustained upon examination, including resolutions of any related appeals or litigation processes, based on the technical merits. The amount recognized is measured as the largest amount of tax benefit that is greater than 50 percent likely of being realized upon effective settlement. Deferred taxes are not provided on undistributed earnings of our foreign operations that are considered to be permanently reinvested.
Foreign Currency Translation	Foreign Currency Translation: The reporting currency of the Company and its subsidiaries is the U.S. dollar. Our foreign subsidiaries generally consider their local currency to be their functional currency. Foreign currency-denominated assets and liabilities of these foreign subsidiaries are translated into U.S. dollars at year-end exchange rates and revenues and expenses are translated at average exchange rates during the corresponding period, and stockholders’ equity accounts are primarily translated at historical exchange rates. Foreign currency translation adjustments are included in other comprehensive income or loss in the statements of consolidated comprehensive income, and the cumulative effect is included in the stockholders’ equity section of the consolidated balance sheets. Realized gains and losses from currency exchange transactions are recorded in operating expenses in the consolidated statements of operations and were not material to our consolidated results of operations in 2016 , 2015 or 2014 . We release cumulative translation adjustment from stockholders’ equity into net income as a gain or loss only upon complete or substantially complete liquidation of a controlling interest in a subsidiary or a group of assets within a foreign entity. We also release all or a pro rata portion of the cumulative translation adjustment into net income upon the sale of an equity method investment that is a foreign entity.
Derivative Financial Instruments	Derivative Financial Instruments: Derivative financial instruments are used principally in the management of foreign currency exchange and interest rate exposures and are recorded on the consolidated balance sheets at fair value. If a derivative is designated as a fair value hedge, the changes in the fair value of the derivative and of the hedged item attributable to the hedged risk are recognized as a charge or credit to earnings. If the derivative is designated as a cash flow hedge, the effective portions of changes in the fair value of the derivative are included in other comprehensive income or loss in the statements of consolidated comprehensive income, and the cumulative effect is included in the stockholders’ equity section of the consolidated balance sheets. The cumulative changes in fair value are reclassified to the consolidated statements of operations when the hedged item affects earnings. We periodically evaluate hedge effectiveness, and ineffective portions of changes in the fair value of cash flow hedges are recognized as a charge or credit to earnings. Derivative instruments not designated as hedges are marked-to-market at the end of each accounting period with the change included in earnings.
Comprehensive Income	Comprehensive Income: Comprehensive income consists of two components, net income and other comprehensive income. Other comprehensive income refers to revenue, expenses, and gains and losses that under GAAP are recorded as an element of stockholders’ equity but are excluded from net income. Our other comprehensive income primarily consists of foreign currency translation adjustments from those subsidiaries where the local currency is the functional currency, unrealized gains and losses on cash flow hedges, as well as unrealized gains and losses on retirement-related benefit plans.
Noncontrolling Interests and Redeemable Noncontrolling Interests	Noncontrolling Interests and Redeemable Noncontrolling Interests: Noncontrolling interests represent the portion of profit or loss, net assets and comprehensive income that is not allocable to McKesson Corporation. In 2016 and 2015, net income attributable to noncontrolling interests primarily represents guaranteed dividends and recurring compensation that McKesson is obligated to pay to the noncontrolling shareholders of Celesio AG (“Celesio”). Noncontrolling interests with redemption features, such as put rights, that are not solely within the Company’s control are considered redeemable noncontrolling interests. Redeemable noncontrolling interests are presented outside of Stockholders’ Equity on our consolidated balance sheet. Refer to Financial Note 10, “Noncontrolling Interests and Redeemable Noncontrolling Interests,” for more information.
Share-Based Compensation	Share-Based Compensation: We account for all share-based compensation transactions using a fair-value based measurement method. The share-based compensation expense, for the portion of the awards that is ultimately expected to vest, is recognized on a straight-line basis over the requisite service period. The compensation expense recognized has been classified in the consolidated statements of operations or capitalized on the consolidated balance sheets in the same manner as cash compensation paid to our employees.
Loss Contingencies	Loss Contingencies: We are subject to various claims, including claims with customers and vendors, pending and potential legal actions for damages, investigations relating to governmental laws and regulations and other matters arising out of the normal conduct of our business. When a loss is considered probable and reasonably estimable, we record a liability in the amount of our best estimate for the ultimate loss. However, the likelihood of a loss with respect to a particular contingency is often difficult to predict and determining a meaningful estimate of the loss or a range of loss may not be practicable based on the information available and the potential effect of future events and decisions by third parties that will determine the ultimate resolution of the contingency. Moreover, it is not uncommon for such matters to be resolved over many years, during which time relevant developments and new information must be reevaluated at least quarterly to determine both the likelihood of potential loss and whether it is possible to reasonably estimate a range of possible loss. When a material loss is probable but a reasonable estimate cannot be made, disclosure of the proceeding is provided. Disclosure is also provided when it is reasonably possible that a loss will be incurred or when it is reasonably possible that the amount of a loss will exceed the recorded provision. We review all contingencies at least quarterly to determine whether the likelihood of loss has changed and to assess whether a reasonable estimate of the loss or range of the loss can be made. As discussed above, development of a meaningful estimate of loss or a range of potential loss is complex when the outcome is directly dependent on negotiations with or decisions by third parties, such as regulatory agencies, the court system and other interested parties. Such factors bear directly on whether it is possible to reasonably estimate a range of potential loss and boundaries of high and low estimate.
Business Combinations	Business Combinations: We account for acquired businesses using the acquisition method of accounting, which requires that once control is obtained of a business, 100% of the assets acquired and liabilities assumed, including amounts attributed to noncontrolling interests, be recorded at the date of acquisition at their respective fair values. Any excess of the purchase price over the estimated fair values of the net assets acquired is recorded as goodwill. Acquisition-related expenses and related restructuring costs are expensed as incurred. Several valuation methods may be used to determine the fair value of assets acquired and liabilities assumed. For intangible assets, we typically use the income method. This method starts with a forecast of all of the expected future net cash flows for each asset. These cash flows are then adjusted to present value by applying an appropriate discount rate that reflects the risk factors associated with the cash flow streams. Some of the more significant estimates and assumptions inherent in the income method or other methods include the amount and timing of projected future cash flows, the discount rate selected to measure the risks inherent in the future cash flows and the assessment of the asset’s life cycle and the competitive trends impacting the asset, including consideration of any technical, legal, regulatory, or economic barriers to entry. Determining the useful life of an intangible asset also requires judgment as different types of intangible assets will have different useful lives and certain assets may even be considered to have indefinite useful lives.
Recently Adopted Accounting Pronouncements and Recently Issued Accounting Pronouncements Not Yet Adopted	Recently Adopted Accounting Pronouncements Deferred Income Taxes : In November 2015, amended guidance was issued for the balance sheet classification of deferred income taxes. The amended guidance requires the classification of all deferred tax assets and liabilities as noncurrent on the balance sheet instead of separating deferred taxes into current and noncurrent amounts. The amended guidance would have been effective for us commencing in the first quarter of 2018, however, early adoption was permitted. We early adopted this amended guidance in the fourth quarter of 2016 on a prospective basis. As a result, we reclassified current net deferred tax liabilities of approximately $2 billion on our consolidated balance sheet as of March 31, 2016. Our March 31, 2015 balances were not retrospectively adjusted. The adoption of this guidance had no impact on our condensed consolidated statements of earnings, comprehensive income or cash flows. This amended guidance only resulted in a change in presentation of our deferred income taxes on our consolidated balance sheet as of March 31, 2016. Discontinued Operations: In the first quarter of 2016, we adopted amended guidance for reporting of discontinued operations and disclosures of disposals of components. The amended guidance revises the criteria for disposals to qualify as discontinued operations and permits significant continuing involvement and continuing cash flows with the discontinued operation. In addition, the amended guidance requires additional disclosures for discontinued operations and new disclosures for individually material disposal transactions that do not meet the definition of a discontinued operation. Refer to Financial Note 5, “Divestiture of Businesses,” for more information regarding the impact of this amended guidance on our consolidated financial statements. Cumulative Translation Adjustment: In the first quarter of 2015, we adopted amended guidance for a parent’s accounting for the cumulative translation adjustment upon derecognition of certain subsidiaries or group of assets within a foreign entity or of an investment in a foreign entity. The amended guidance requires the release of any cumulative translation adjustment into net income only upon complete or substantially complete liquidation of a controlling interest in a subsidiary or a group of assets within a foreign entity. Also, it requires the release of all or a pro rata portion of the cumulative translation adjustment to net income in the case of sale of an equity method investment that is a foreign entity. The adoption of this amended guidance did not have a material effect on our consolidated financial statements. Recently Issued Accounting Pronouncements Not Yet Adopted Share-Based Payments: In March 2016, amended guidance was issued for employee share-based payment awards. The amended guidance makes several modifications related to the accounting for forfeitures, employer tax withholding on share-based compensation and excess tax benefits or deficiencies. The amended guidance also clarifies the statement of cash flows presentation for share-based awards. The amended guidance is effective for us prospectively commencing in the first quarter of 2018. Early adoption is permitted. We are currently evaluating the impact of this amended guidance on our consolidated financial statements. Investments: In March 2016, amended guidance was issued to simplify the transition to the equity method of accounting. This standard eliminates the requirement that when an existing cost method investment qualifies for use of the equity method, an investor must restate its historical financial statements, as if the equity method had been used during all previous periods. Additionally, at the point an investment qualifies for the equity method, any unrealized gain or loss in accumulated other comprehensive income (loss) will be recognized through earnings. The amended guidance is effective for us prospectively commencing in the first quarter of 2018. Early adoption is permitted. We are currently evaluating the impact of this amended guidance on our consolidated financial statements. Derivatives and Hedging: In March 2016, amended guidance was issued for derivative instrument novations. The amendments clarify that a novation, a change in the counterparty, to a derivative instrument that has been designated as a hedging instrument does not, in and of itself, require dedesignation of that hedging relationships provided all other hedge accounting criteria continue to be met. The amended guidance is effective for us commencing in the first quarter of 2018, The amended guidance allows for either prospective or modified retrospective adoption. Early adoption is permitted. We are currently evaluating the impact of this amended guidance on our consolidated financial statements. Leases: In February 2016, amended guidance was issued for lease arrangements. The amended standard will require recognition on the balance sheet for all leases with terms longer than 12 months: a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. The amended guidance is effective for us commencing in the first quarter of 2020, on a modified retrospective basis. Early adoption is permitted. We are currently evaluating the impact of this amended guidance on our consolidated financial statements. Financial Instruments: In January 2016, amended guidance was issued that requires equity investments to be measured at fair value with changes in fair value recognized in net income and enhanced disclosures about those investments. This guidance also simplifies the impairment assessments of equity investments without readily determinable fair value. The investments that are accounted for under the equity method of accounting or result in consolidation of the investee are excluded from the scope of this amended guidance. The amended guidance will become effective for us commencing in the first quarter of 2019 and will be adopted through a cumulative-effect adjustment. Early adoption is not permitted except for certain provisions. We are currently evaluating the impact of this amended guidance on our consolidated financial statements. Business Combinations: In September 2015, amended guidance was issued for an acquirer’s accounting for measurement-period adjustments. The amended guidance eliminates the requirement that an acquirer in a business combination account for measurement-period adjustments retrospectively and instead requires that measurement-period adjustments be recognized during the period in which it determines the adjustment. In addition, the amended guidance requires that the acquirer record, in the same period’s financial statements, the effect on earnings of changes in depreciation, amortization, or other income effects, if any, as a result of the change to the provisional amounts, calculated as if the accounting had been completed at the acquisition date. The amended guidance is effective for us prospectively commencing in the first quarter of 2017. Early adoption is permitted. We do not expect the adoption of this amended guidance to have a material effect on our consolidated financial statements. Inventory: In July 2015, amended guidance was issued for the subsequent measurement of inventory. The amended guidance requires entities to measure inventory at the lower of cost or net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. The requirement would replace the current lower of cost or market evaluation. Accounting guidance is unchanged for inventory measured using last-in, first-out (“LIFO”) or the retail method. The amended guidance will become effective for us commencing in the first quarter of 2018. Early adoption is permitted. We are currently evaluating the impact of this amended guidance on our consolidated financial statements. Fair Value Measurement: In May 2015, amended guidance was issued that limits disclosures and removes the requirement to categorize investments within the fair value hierarchy if the fair value of the investment is measured using the net asset value per share practical expedient. The amended guidance will become effective for us commencing in the first quarter of 2017. Early adoption is permitted. This amended guidance is primarily expected to affect our annual disclosures related to our pension benefits. We do not expect the adoption of this amended guidance to have a material effect on our consolidated financial statements. Fees Paid in a Cloud Computing Arrangement : In April 2015, amended guidance was issued for a customer’s accounting for fees paid in a cloud computing arrangement. The amended guidance requires customers to determine whether or not an arrangement contains a software license element. If the arrangement contains a software element, the related fees paid should be accounted for as an acquisition of a software license. If the arrangement does not contain a software license, it is accounted for as a service contract. The amended guidance will become effective for us commencing in the first quarter of 2017. Early adoption is permitted. We do not expect the adoption of this amended guidance to have a material effect on our consolidated financial statements. Debt Issuance Costs : In April 2015, amended guidance was issued for the balance sheet presentation of debt issuance costs. The amended guidance requires debt issuance costs related to a recognized debt liability to be reported in the balance sheet as a direct deduction from the carrying amount of that debt liability. The recognition and measurement guidance for debt issuance costs are not affected by the amended guidance. In August 2015, a clarification was added to this amended guidance that debt issuance costs related to line-of-credit arrangements can continue to be deferred and presented as an asset on the balance sheet. The amended guidance will become effective for us commencing in the first quarter of 2017. Early adoption is permitted. We do not expect the adoption of this amended guidance to have a material effect on our consolidated financial statements. Consolidation: In February 2015, amended guidance was issued for consolidating legal entities in which a reporting entity holds a variable interest. The amended guidance modifies the evaluation of whether limited partnerships and similar legal entities are VIEs and changes the consolidation analysis of reporting entities that are involved with VIEs that have fee arrangements and related party relationships. The amended guidance will become effective for us commencing in the first quarter of 2017. Early adoption is permitted. We do not expect the adoption of this amended guidance to have a material effect on our consolidated financial statements. Revenue Recognition: In May 2014, amended guidance was issued for recognizing revenue from contracts with customers. The amended guidance eliminates industry specific guidance and applies to all companies. Revenues will be recognized when an entity satisfies a performance obligation by transferring control of a promised good or service to a customer in an amount that reflects the consideration to which the entity expects to be entitled for that good or service. Revenue from a contract that contains multiple performance obligations is allocated to each performance obligation generally on a relative standalone selling price basis. The amended guidance also requires additional quantitative and qualitative disclosures. In March 2016, amended guidance was issued to clarify implementation guidance on principal versus agent considerations. In April 2016, another amended guidance was issued to permit an entity, as an accounting policy election, to account for shipping and handling activities that occur after the customer has obtained control of a good as an activity to fulfill the promise to transfer the good. The April 2016 amendment also provided clarifications on determining whether a promised license provides a customer with a right to use or a right to access an entity’s intellectual property. These amended standards are all effective for us commencing in the first quarter of 2019 and allow for either full retrospective adoption or modified retrospective adoption. Early adoption is permitted but not prior to our first quarter of 2018. We are currently evaluating the impact of this amended guidance on our consolidated financial statements.

Restructuring (Tables)

Restructuring (Tables)	12 Months Ended
	Mar. 31, 2016
Restructuring and Related Activities [Abstract]
Summary of details for charges recorded	Restructuring charges for our Cost Alignment Plan during the fourth quarter of 2016 consisted of the following: (In millions) Distribution Solutions Technology Solutions Corporate Total Severance and employee-related costs, net (1) $ 147 $ 44 $ 16 $ 207 Exit-related costs 3 1 1 5 Asset impairments and accelerated depreciation and amortization (2) 11 6 — 17 Total $ 161 $ 51 $ 17 $ 229 Cost of Sales $ 5 $ 21 $ — $ 26 Operating Expenses 156 30 17 203 Total $ 161 $ 51 $ 17 $ 229 (1) Severance and employee-related costs, net, include charges of $117 million and $90 million , for a total of $207 million , for a reduction in workforce and business process initiatives. (2) Asset impairments and accelerated depreciation and amortization charges primarily include impairments for capitalized software projects and software licenses due to abandonments.
Summary of activity related to the restructuring liabilities	The following table summarizes the activity related to the restructuring liabilities associated with the Cost Alignment Plan for the quarter and year ended March 31, 2016: Quarter and Year Ended March 31, 2016 (In millions) Balance March 31, 2015 Net restructuring charges recognized Non-cash charges Cash Payments Other Balance March 31, 2016 (1) 2016 Cost Alignment Plan Distribution Solutions $ — $ 161 $ (4 ) $ (1 ) $ — $ 156 Technology Solutions — 51 (3 ) — (3 ) 45 Corporate — 17 5 — (1 ) 21 Total 2016 Cost Alignment Plan $ — $ 229 $ (2 ) $ (1 ) $ (4 ) $ 222 (1) The reserve balances as of March 31, 2016 include $172 million recorded in other accrued liabilities and $50 million recorded in other noncurrent liabilities in our consolidated balance sheet.

Share-Based Compensation (Table

Share-Based Compensation (Tables)	12 Months Ended
	Mar. 31, 2016
Share-based Compensation [Abstract]
Schedule of components of share-based compensation expense and related tax benefits	The components of share-based compensation expense and related tax benefits are as follows: Years Ended March 31, (In millions) 2016 2015 2014 Restricted stock unit awards (1) $ 88 $ 137 $ 126 Stock options 22 24 22 Employee stock purchase plan 13 13 12 Share-based compensation expense (2) 123 174 160 Tax benefit for share-based compensation expense (3) (41 ) (61 ) (55 ) Share-based compensation expense, net of tax $ 82 $ 113 $ 105 (1) Includes compensation expense recognized for RSUs, PeRSUs and TSRUs. Our TSRUs were awarded beginning in 2015. (2) 2016 includes non-cash credits of $14 million representing the reversal of previously recognized share-based compensation, which was recorded due to employee terminations associated with the March 2016 restructuring plan. (3) Income tax benefit is computed using the tax rates of applicable tax jurisdictions. Additionally, a portion of pre-tax compensation expense is not tax-deductible.
Schedule of weighted-average assumptions used to estimate the fair value	The weighted-average assumptions used to estimate the fair value of TSRUs are as follows: Years Ended March 31, 2016 2015 Expected stock price volatility 18% 21% Expected dividend yield 0.4% 0.5% Risk-free interest rate 0.9% 0.7% Expected life (in years) 3 3 Weighted-average assumptions used to estimate the fair value of employee stock options were as follows: Years Ended March 31, 2016 2015 2014 Expected stock price volatility 21% 22% 22% Expected dividend yield 0.4% 0.6% 0.7% Risk-free interest rate 1.4% 1.3% 0.7% Expected life (in years) 4 4 4
Summary of options outstanding	The following is a summary of stock options outstanding at March 31, 2016 : Options Outstanding Options Exercisable Range of Exercise Prices Number of Options Outstanding at Year End (In millions) Weighted- Average Remaining Contractual Life (Years) Weighted- Average Exercise Price Number of Options Exercisable at Year End (In millions) Weighted- Average Exercise Price $ 40.46 – $ 140.19 3 2 $ 83.62 2 $ 78.01 140.20 – 239.93 1 6 206.58 — 180.24 4 2
Summary of stock option activity	The following table summarizes stock option activity during 2016 : (In millions, except per share data) Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (Years) Aggregate Intrinsic Value (2) Outstanding, March 31, 2015 5 $ 95.01 4 $ 539 Granted 1 236.77 Cancelled (1) 149.19 Exercised (1) 63.75 Outstanding, March 31, 2016 4 $ 118.95 3 $ 201 Vested and expected to vest (1) 3 $ 118.21 3 $ 200 Vested and exercisable, March 31, 2016 2 85.15 2 173 (1) The number of options expected to vest takes into account an estimate of expected forfeitures. (2) The intrinsic value is calculated as the difference between the period-end market price of the Company’s common stock and the exercise price of “in-the-money” options.
Summary of data related to stock option activity	The following table provides data related to stock option activity: Years Ended March 31, (In millions, except per share data) 2016 2015 2014 Weighted-average grant date fair value per stock option $ 44.04 $ 35.49 $ 21.45 Aggregate intrinsic value on exercise $ 107 $ 153 $ 144 Cash received upon exercise $ 47 $ 76 $ 111 Tax benefits realized related to exercise $ 42 $ 60 $ 55 Total fair value of stock options vested $ 18 $ 20 $ 24 Total compensation cost, net of estimated forfeitures, related to unvested stock options not yet recognized, pre-tax $ 20 $ 22 $ 29 Weighted-average period in years over which stock option compensation cost is expected to be recognized 2 2 1
Summary of restricted stock unit award activity	The following table summarizes restricted stock unit award activity during 2016 : (In millions, except per share data) Shares Weighted- Average Grant Date Fair Value Per Share Nonvested, March 31, 2015 4 $ 129.57 Granted 1 240.35 Cancelled (1) 159.17 Vested (1) 89.44 Nonvested, March 31, 2016 3 $ 176.59
Schedule of data related to restricted stock unit award activity	The following table provides data related to restricted stock unit award activity: Years Ended March 31, (In millions) 2016 2015 2014 Total fair value of shares vested $ 104 $ 126 $ 184 Total compensation cost, net of estimated forfeitures, related to nonvested restricted stock unit awards not yet recognized, pre-tax $ 144 $ 206 $ 236 Weighted-average period in years over which restricted stock unit award cost is expected to be recognized 2 2 2

Other Income, Net (Tables)

Other Income, Net (Tables)	12 Months Ended
	Mar. 31, 2016
Other Nonoperating Income (Expense) [Abstract]
Schedule of other income, net	Years Ended March 31, (In millions) 2016 2015 2014 Interest income $ 18 $ 20 $ 16 Equity in earnings, net (1) 15 12 — Other, net (1) 25 31 16 Total $ 58 $ 63 $ 32 (1) Primarily recorded within our Distribution Solutions segment.

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Mar. 31, 2016
Income Tax Disclosure [Abstract]
Schedule of income from continuing operations before income taxes	Years Ended March 31, (In millions) 2016 2015 2014 Income from continuing operations before income taxes U.S. $ 2,319 $ 1,893 $ 1,554 Foreign 931 764 617 Total income from continuing operations before income taxes $ 3,250 $ 2,657 $ 2,171
Schedule of income tax expense related to continuing operations	Income tax expense related to continuing operations consists of the following: Years Ended March 31, (In millions) 2016 2015 2014 Current Federal $ 658 $ 453 $ 484 State 96 90 64 Foreign 90 101 193 Total current 844 644 741 Deferred Federal 95 195 24 State 42 53 10 Foreign (73 ) (77 ) (18 ) Total deferred 64 171 16 Income tax expense $ 908 $ 815 $ 757
Schedule of reconciliation between effective tax rate on income from continuing operations and statutory tax rate	The reconciliation between our effective tax rate on income from continuing operations and statutory tax rate is as follows: Years Ended March 31, (In millions) 2016 2015 2014 Income tax expense at federal statutory rate $ 1,137 $ 930 $ 760 State income taxes net of federal tax benefit 92 81 57 Foreign income taxed at various rates (295 ) (247 ) (177 ) Canadian litigation (8 ) — 122 Controlled substance distribution reserve — 58 — Unrecognized tax benefits and settlements (6 ) 10 (6 ) Tax credits (18 ) (10 ) (6 ) Other, net 6 (7 ) 7 Income tax expense $ 908 $ 815 $ 757
Schedule of deferred tax balances	Deferred tax balances consisted of the following: March 31, (In millions) 2016 2015 Assets Receivable allowances $ 110 $ 83 Deferred revenue 77 72 Compensation and benefit related accruals 710 681 Net operating loss and credit carryforwards 367 316 Other 275 266 Subtotal 1,539 1,418 Less: valuation allowance (267 ) (229 ) Total assets 1,272 1,189 Liabilities Inventory valuation and other assets (2,619 ) (2,333 ) Fixed assets and systems development costs (326 ) (324 ) Intangibles (981 ) (1,073 ) Other (21 ) (61 ) Total liabilities (3,947 ) (3,791 ) Net deferred tax liability $ (2,675 ) $ (2,602 ) Current net deferred tax asset (1) $ — $ 27 Current net deferred tax liability (1) — (1,820 ) Long-term deferred tax asset 59 50 Long-term deferred tax liability (2,734 ) (859 ) Net deferred tax liability $ (2,675 ) $ (2,602 ) (1) Upon the adoption of the amended accounting guidance, we reclassified current net deferred tax liabilities and current net deferred tax assets as noncurrent on our consolidated balance sheet as of March 31, 2016. Our March 31, 2015 balances were not retrospectively reclassified.
Schedule of gross unrecognized tax benefits	The following table summarizes the activity related to our gross unrecognized tax benefits for the last three years: Years Ended March 31, (In millions) 2016 2015 2014 Unrecognized tax benefits at beginning of period $ 616 $ 647 $ 560 Additions based on tax positions related to prior years 116 62 106 Reductions based on tax positions related to prior years (62 ) (18 ) (23 ) Additions based on tax positions related to current year 28 27 23 Reductions based on settlements (141 ) (65 ) (4 ) Reductions based on the lapse of the applicable statutes of limitations (6 ) (12 ) (7 ) Exchange rate fluctuations 4 (25 ) (8 ) Unrecognized tax benefits at end of period $ 555 $ 616 $ 647

Discontinued Operations (Tables

Discontinued Operations (Tables)	12 Months Ended
	Mar. 31, 2016
Discontinued Operations and Disposal Groups [Abstract]
Schedule of results for discontinued operations	A summary of results of discontinued operations is as follows: Years Ended March 31, (In millions) 2016 2015 2014 Revenues $ 1,603 $ 2,196 $ 637 Loss from discontinued operations $ (24 ) $ (321 ) $ (177 ) Loss on sale — (6 ) (5 ) Loss from discontinued operations before income tax (24 ) (327 ) (182 ) Income tax (expense) benefit (8 ) 28 26 Loss from discontinued operations, net of tax $ (32 ) $ (299 ) $ (156 ) A summary of carrying amounts of major classes of assets and liabilities included as part of discontinued operations is as follow: March 31, (In millions) 2016 2015 Receivables, net $ 289 $ 314 Inventories, net 266 254 Other assets 80 92 Total assets of discontinued operations (1) 635 660 Drafts and account payable 264 209 Short-term borrowings 142 126 Other liabilities 254 328 Total liabilities of discontinued operations (1) $ 660 $ 663 (1) Assets and liabilities of discontinued operations are included under the captions “Prepaid expenses and other” and “Other accrued liabilities” within our consolidated balance sheets.

Noncontrolling Interests and 44

Noncontrolling Interests and Redeemable Noncontrolling Interests (Tables)	12 Months Ended
	Mar. 31, 2016
Noncontrolling Interest [Abstract]
Schedule of changes in noncontrolling interests and redeemable noncontrolling interests	Changes in noncontrolling interests and redeemable noncontrolling interests were as follows: (In millions) Noncontrolling interests Redeemable Noncontrolling Interests Balance, March 31, 2014 $ 1,796 $ — Net income attributable to noncontrolling interests (1) 5 62 Other comprehensive loss (174 ) (105 ) Purchase of noncontrolling interests (2) (3) (4) (60 ) (9 ) Reclassification from Total Equity to Redeemable Noncontrolling Interests (5) (1,500 ) 1,500 Reclassification of guaranteed dividends and recurring compensation to other accrued liabilities — (62 ) Other 17 — Balance, March 31, 2015 84 1,386 Net income attributable to noncontrolling interests (1) 8 44 Other comprehensive loss — 20 Reclassification of recurring compensation to other accrued liabilities — (44 ) Other (8 ) — Balance, March 31, 2016 $ 84 $ 1,406 (1) Redeemable noncontrolling interests for 2015 include the Guaranteed Dividend of $50 million and the Compensation Amount of $12 million , and for 2016 include the Compensation Amount of $44 million . (2) Includes $35 million decrease in noncontrolling interests resulting from the April 2014 completion of McKesson’s tender offer for approximately 1 million additional Celesio shares. (3) Includes $25 million decrease in noncontrolling interests resulting from the July 2014 purchase of the remaining ownership interests in a wholesale distributor in Brazil. (4) Decrease in redeemable noncontrolling interests reflects the exercise of the Put Right by the noncontrolling shareholders of Celesio. (5) Includes net foreign currency losses of $138 million attributable to noncontrolling interests

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	12 Months Ended
	Mar. 31, 2016
Earnings Per Share [Abstract]
Schedule of basic and diluted earnings per common share	The computations for basic and diluted earnings per common share are as follows: Years Ended March 31, (In millions, except per share amounts) 2016 2015 2014 Income from continuing operations $ 2,342 $ 1,842 $ 1,414 Net (income) loss attributable to noncontrolling interests (52 ) (67 ) 5 Income from continuing operations attributable to McKesson 2,290 1,775 1,419 Loss from discontinued operations, net of tax (32 ) (299 ) (156 ) Net income attributable to McKesson $ 2,258 $ 1,476 $ 1,263 Weighted average common shares outstanding: Basic 230 232 229 Effect of dilutive securities: Options to purchase common stock 1 1 1 Restricted stock units 2 2 3 Diluted 233 235 233 Earnings (loss) per common share attributable to McKesson: (1) Diluted Continuing operations $ 9.84 $ 7.54 $ 6.08 Discontinued operations (0.14 ) (1.27 ) (0.67 ) Total $ 9.70 $ 6.27 $ 5.41 Basic Continuing operations $ 9.96 $ 7.66 $ 6.19 Discontinued operations (0.14 ) (1.29 ) (0.68 ) Total $ 9.82 $ 6.37 $ 5.51 (1) Certain computations may reflect rounding adjustments.

Receivables, Net (Tables)

Receivables, Net (Tables)	12 Months Ended
	Mar. 31, 2016
Receivables, Net, Current [Abstract]
Schedule of receivables	March 31, (In millions) 2016 2015 Customer accounts $ 14,519 $ 13,117 Other 3,711 2,965 Total 18,230 16,082 Allowances (250 ) (168 ) Net $ 17,980 $ 15,914

Property, Plant and Equipment47

Property, Plant and Equipment, Net (Tables)	12 Months Ended
	Mar. 31, 2016
Property, Plant and Equipment, Net [Abstract]
Schedule of property, plant and equipment, net	March 31, (In millions) 2016 2015 Land $ 228 $ 207 Building, machinery, equipment and other 3,556 3,237 Total property, plant and equipment 3,784 3,444 Accumulated depreciation (1,506 ) (1,399 ) Property, plant and equipment, net $ 2,278 $ 2,045

Goodwill and Intangible Asset48

Goodwill and Intangible Assets, Net (Tables)	12 Months Ended
	Mar. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of changes in the carrying amount of goodwill	Changes in the carrying amount of goodwill were as follows: (In millions) Distribution Solutions Technology Solutions Total Balance, March 31, 2014 $ 8,078 $ 1,849 $ 9,927 Goodwill acquired 93 — 93 Amount reclassified to assets held-for-sale (14 ) (1 ) (15 ) Acquisition accounting, transfers and other adjustments 625 — 625 Foreign currency translation adjustments, net (788 ) (25 ) (813 ) Balance, March 31, 2015 $ 7,994 $ 1,823 $ 9,817 Goodwill acquired 21 — 21 Acquisition accounting, transfers and other adjustments 8 — 8 Goodwill disposed (59 ) (27 ) (86 ) Foreign currency translation adjustments, net 23 3 26 Balance, March 31, 2016 $ 7,987 $ 1,799 $ 9,786
Schedule of information regarding intangible assets	Information regarding intangible assets is as follows: March 31, 2016 March 31, 2015 (Dollars in millions) Weighted Average Remaining Amortization Period (Years) Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Customer lists 7 $ 2,652 $ (1,324 ) $ 1,328 $ 2,683 $ (1,116 ) $ 1,567 Service agreements 14 959 (269 ) 690 957 (215 ) 742 Pharmacy licenses 25 857 (121 ) 736 874 (65 ) 809 Trademarks and trade names 14 314 (96 ) 218 315 (82 ) 233 Technology 2 195 (182 ) 13 213 (184 ) 29 Other 3 163 (127 ) 36 162 (101 ) 61 Total $ 5,140 $ (2,119 ) $ 3,021 $ 5,204 $ (1,763 ) $ 3,441

Capitalized Software Held for49

Capitalized Software Held for Sale, Net (Tables)	12 Months Ended
	Mar. 31, 2016
Capitalized Computer Software, Net [Abstract]
Schedule of changes in the carrying amount of capitalized software held for sale, net	Changes in the carrying amount of capitalized software held for sale, net, which is included in other assets in the consolidated balance sheets, were as follows: Years Ended March 31, (In millions) 2016 2015 2014 Balance, at beginning of period $ 91 $ 103 $ 126 Amounts capitalized 30 34 40 Amortization expense (37 ) (40 ) (50 ) Impairment charges — — (12 ) Disposal (5 ) — — Foreign currency translations adjustments, net (1 ) (6 ) (1 ) Balance, at end of period $ 78 $ 91 $ 103

Debt and Financing Activities (

Debt and Financing Activities (Tables)	12 Months Ended
	Mar. 31, 2016
Debt Disclosure [Abstract]
Schedule of long-term debt	Long-term debt consisted of the following: March 31, (In millions) 2016 2015 U.S. Dollar notes (1) Floating Rate Notes due September 10, 2015 $ — $ 400 0.95% Notes due December 4, 2015 — 500 3.25% Notes due March 1, 2016 — 600 5.70% Notes due March 1, 2017 500 500 1.29% Notes due March 10, 2017 700 700 1.40% Notes due March 15, 2018 500 499 7.50% Notes due February 15, 2019 350 349 2.28% Notes due March 15, 2019 1,100 1,100 4.75% Notes due March 1, 2021 599 599 2.70% Notes due December 15, 2022 400 400 2.85% Notes due March 15, 2023 400 400 3.80% Notes due March 15, 2024 1,100 1,100 7.65% Debentures due March 1, 2027 175 175 6.00% Notes due March 1, 2041 493 493 4.88% Notes due March 15, 2044 800 800 Foreign currency notes (2) 4.00% Bonds due October 18, 2016 403 388 4.50% Bonds due April 26, 2017 583 563 Lease and other obligations 44 143 Total debt 8,147 9,709 Less current portion (1,612 ) (1,529 ) Total long-term debt $ 6,535 $ 8,180 (1) Interest on these notes is payable semiannually each year. These notes are unsecured and unsubordinated obligations of the Company. (2) Interest on these Euro-denominated bonds is due annually each year.

Pension Benefits (Tables)

Pension Benefits (Tables)	12 Months Ended
	Mar. 31, 2016
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]
Schedule of net periodic expense for pension plans	The net periodic expense for our pension plans, which includes net pension expense of Celesio beginning February 2014, is as follows: U.S. Plans Non-U.S. Plans Years Ended March 31, Years Ended March 31, (In millions) 2016 2015 2014 2016 2015 2014 Service cost - benefits earned during the year $ 4 $ 1 $ 4 $ 20 $ 16 $ 6 Interest cost on projected benefit obligation 18 19 19 24 34 11 Expected return on assets (19 ) (21 ) (20 ) (30 ) (30 ) (12 ) Amortization of unrecognized actuarial loss, prior service costs and net transitional obligation 42 19 32 3 3 4 Curtailment/settlement loss (gain) 2 — — — 6 (1 ) Net periodic pension expense $ 47 $ 18 $ 35 $ 17 $ 29 $ 8 The net periodic expense for our postretirement welfare benefits is as follows: Years Ended March 31, (In millions) 2016 2015 2014 Service cost - benefits earned during the year $ 1 $ 1 $ 2 Interest cost on accumulated benefit obligation 4 5 5 Amortization of unrecognized actuarial gain and prior service credit — (4 ) (1 ) Curtailment gain — — (2 ) Net periodic postretirement expense $ 5 $ 2 $ 4
Schedule of changes in benefit obligations and plan assets for pension plans	Information regarding the changes in benefit obligations and plan assets for our pension plans is as follows: U.S. Plans Non-U.S. Plans Years Ended March 31, Years Ended March 31, (In millions) 2016 2015 2016 2015 Change in benefit obligations Benefit obligation at beginning of period (1) $ 583 $ 540 $ 963 $ 934 Service cost 4 1 20 16 Interest cost 18 19 24 34 Actuarial loss (gain) (13 ) 53 (64 ) 194 Benefit payments (54 ) (30 ) (35 ) (49 ) Amendments — — (2 ) (6 ) Expenses paid (3 ) — — — Foreign exchange impact and other — — (7 ) (160 ) Benefit obligation at end of period (1) $ 535 $ 583 $ 899 $ 963 Change in plan assets Fair value of plan assets at beginning of period $ 298 $ 300 $ 612 $ 590 Actual return on plan assets (3 ) 16 2 88 Employer and participant contributions 24 12 44 73 Benefits paid (54 ) (30 ) (35 ) (49 ) Expenses paid (3 ) — — — Foreign exchange impact and other — — (16 ) (90 ) Fair value of plan assets at end of period $ 262 $ 298 $ 607 $ 612 Funded status at end of period $ (273 ) $ (285 ) $ (292 ) $ (351 ) Amounts recognized on the balance sheet Assets $ — $ — $ 21 $ — Current liabilities (2 ) (17 ) (11 ) (6 ) Long-term liabilities (271 ) (268 ) (302 ) (345 ) Total $ (273 ) $ (285 ) $ (292 ) $ (351 ) (1) The benefit obligation is the projected benefit obligation.
Schedule of projected benefit obligation, accumulated benefit obligation and fair value of plan assets for pension plans	The following table provides the projected benefit obligation, accumulated benefit obligation and fair value of plan assets for all our pension plans with an accumulated benefit obligation in excess of plan assets. U.S. Plans Non-U.S. Plans March 31, March 31, (In millions) 2016 2015 2016 2015 Projected benefit obligation $ 535 $ 583 $ 899 $ 963 Accumulated benefit obligation 535 583 855 897 Fair value of plan assets 262 298 607 612
Schedule of defined benefit plan amounts recognized in other comprehensive income (loss)	Amounts recognized in accumulated other comprehensive income (pre-tax) consist of: U.S. Plans Non-U.S. Plans March 31, March 31, (In millions) 2016 2015 2016 2015 Net actuarial loss $ 185 $ 220 $ 133 $ 175 Prior service credit — — (11 ) (6 ) Total $ 185 $ 220 $ 122 $ 169
Schedule of other changes in plan assets and benefit obligations recognized in other comprehensive income	Other changes in accumulated other comprehensive income (pre-tax) were as follows: U.S. Plans Non-U.S. Plans Years Ended March 31, Years Ended March 31, (In millions) 2016 2015 2014 2016 2015 2014 Net actuarial loss (gain) $ 9 $ 58 $ (31 ) $ (38 ) $ 117 $ 12 Prior service credit — — (8 ) (5 ) (8 ) — Amortization of: Net actuarial loss (44 ) (27 ) (32 ) (5 ) (5 ) (4 ) Prior service credit (cost) — 8 — 2 2 2 Foreign exchange impact and other — — (1 ) (1 ) (8 ) 4 Total recognized in other comprehensive loss (income) $ (35 ) $ 39 $ (72 ) $ (47 ) $ 98 $ 14
Schedule of weighted-average assumptions used to estimate net periodic pension expense and actuarial present value of benefit obligations	Weighted-average assumptions used to estimate the net periodic pension expense and the actuarial present value of benefit obligations were as follows: U.S. Plans Non-U.S. Plans Years Ended March 31, Years Ended March 31, 2016 2015 2014 2016 2015 2014 Net periodic pension expense Discount rates 3.36 % 3.74 % 3.39 % 2.36 % 3.85 % 3.95 % Rate of increase in compensation 4.00 4.00 4.00 2.80 3.11 2.66 Expected long-term rate of return on plan assets 6.75 7.25 7.25 4.87 5.39 5.71 Benefit obligation Discount rates 3.27 % 3.18 % 3.58 % 2.84 % 2.50 % 3.92 % Rate of increase in compensation 4.00 4.00 4.00 2.98 3.24 3.27
Schedule of sensitivity to changes in weighted-average discount rate for U.S. pension plans	Sensitivity to changes in the weighted-average discount rate for our pension plans is as follows: U.S. Plans Non-U.S. Plans (In millions) One Percentage Point Increase One Percentage Point Decrease One Percentage Point Increase One Percentage Point Decrease Increase (decrease) on projected benefit obligation $ (35) $ 41 $ (85) $ 101 Increase (decrease) on net periodic pension cost — — (4) 6
Summary of pension plan assets using fair value hierarchy by asset class	The following tables represent our pension plan assets as of March 31, 2016 and 2015 , using the fair value hierarchy by asset class. The fair value hierarchy has three levels based on the reliability of the inputs used to determine fair value. Level 1 refers to fair values determined based on unadjusted quoted prices in active markets for identical assets. Level 2 refers to fair values estimated using significant other observable inputs and Level 3 includes fair values estimated using significant unobservable inputs. U.S. Plans Non-U.S. Plans March 31, 2016 March 31, 2016 (In millions) Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Cash and cash equivalents $ 4 $ — $ — $ 4 $ 4 $ — $ — $ 4 Equity securities: Common and preferred stock 16 — — 16 — — — — Equity commingled funds — 165 — 165 6 150 — 156 Fixed income securities: Government securities — 12 — 12 23 68 — 91 Corporate bonds — 12 — 12 1 14 — 15 Mortgage-backed securities — 14 — 14 — — — — Asset-backed securities and other — 22 — 22 — — — — Fixed income commingled funds — — — — 66 120 — 186 Other: Real estate funds — — 17 17 — — 24 24 Other — — — — 21 107 3 131 Total $ 20 $ 225 $ 17 $ 262 $ 121 $ 459 $ 27 $ 607 U.S. Plans Non-U.S. Plans March 31, 2015 March 31, 2015 (In millions) Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Cash and cash equivalents $ 55 $ 1 $ — $ 56 $ 8 $ — $ — $ 8 Equity securities: Common and preferred stock 18 — — 18 — — — — Equity commingled funds — 138 — 138 7 149 — 156 Fixed income securities: Government securities — 14 — 14 26 53 — 79 Corporate bonds — 14 — 14 — 13 — 13 Mortgage-backed securities — 14 — 14 — — — — Asset-backed securities and other — 26 — 26 — — — — Fixed income commingled funds — — — — 64 127 — 191 Other: Real estate funds — — 18 18 — — 26 26 Other commingled funds — — — — — 13 — 13 Other — — — — 7 115 4 126 Total $ 73 $ 207 $ 18 $ 298 $ 112 $ 470 $ 30 $ 612
Schedule of reconciliation of level 3 plan assets held	The following table represents a reconciliation of Level 3 plan assets held during the years ended March 31, 2016 and 2015 : U.S. Plans Non-U.S. Plans (In millions) Real Estate Funds Total Real Estate Funds Other Total Balance at March 31, 2014 $ 16 $ 16 $ 7 $ 5 $ 12 Acquisitions — — — — — Unrealized gain on plan assets still held 2 2 1 — 1 Purchases, sales and settlements — — 18 (1 ) 17 Balance at March 31, 2015 $ 18 $ 18 $ 26 $ 4 $ 30 Acquisitions — — — — — Unrealized gain on plan assets still held 1 1 (2 ) (1 ) (3 ) Purchases, sales and settlements (2 ) (2 ) — — — Balance at March 31, 2016 $ 17 $ 17 $ 24 $ 3 $ 27

Postretirement Benefits (Tables

Postretirement Benefits (Tables)	12 Months Ended
	Mar. 31, 2016
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]
Schedule of net periodic expense for postretirement welfare benefits	The net periodic expense for our pension plans, which includes net pension expense of Celesio beginning February 2014, is as follows: U.S. Plans Non-U.S. Plans Years Ended March 31, Years Ended March 31, (In millions) 2016 2015 2014 2016 2015 2014 Service cost - benefits earned during the year $ 4 $ 1 $ 4 $ 20 $ 16 $ 6 Interest cost on projected benefit obligation 18 19 19 24 34 11 Expected return on assets (19 ) (21 ) (20 ) (30 ) (30 ) (12 ) Amortization of unrecognized actuarial loss, prior service costs and net transitional obligation 42 19 32 3 3 4 Curtailment/settlement loss (gain) 2 — — — 6 (1 ) Net periodic pension expense $ 47 $ 18 $ 35 $ 17 $ 29 $ 8 The net periodic expense for our postretirement welfare benefits is as follows: Years Ended March 31, (In millions) 2016 2015 2014 Service cost - benefits earned during the year $ 1 $ 1 $ 2 Interest cost on accumulated benefit obligation 4 5 5 Amortization of unrecognized actuarial gain and prior service credit — (4 ) (1 ) Curtailment gain — — (2 ) Net periodic postretirement expense $ 5 $ 2 $ 4
Schedule of changes in benefit obligations for postretirement welfare plans	Information regarding the changes in benefit obligations for our postretirement welfare plans is as follows: Years Ended March 31, (In millions) 2016 2015 Benefit obligation at beginning of period $ 118 $ 119 Service cost 1 1 Interest cost 4 5 Plan amendments (16 ) — Actuarial loss 3 5 Benefit payments (11 ) (12 ) Curtailment gain (1 ) — Benefit obligation at end of period $ 98 $ 118

Hedging Activities (Tables)

Hedging Activities (Tables)	12 Months Ended
	Mar. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of information regarding fair value of derivatives on a gross basis	Information regarding the fair value of derivatives on a gross basis is as follows: Balance Sheet Caption March 31, 2016 March 31, 2015 Fair Value of Derivative U.S. Dollar Notional Fair Value of Derivative U.S. Dollar Notional (In millions) Asset Liability Asset Liability Derivatives designated for hedge accounting Foreign exchange contracts (current) Prepaid expenses and other $ 16 $ — $ 80 $ 14 $ — $ 76 Foreign exchange contracts (non-current) Other Noncurrent Assets 46 — 243 53 — 323 Cross currency swaps (non-current) Other Noncurrent Liabilities — 8 546 — — — Total $ 62 $ 8 $ 67 $ — Derivatives not designated for hedge accounting Foreign exchange contracts (current) Prepaid expenses and other $ 23 $ — $ 680 $ 7 $ — $ 493 Foreign exchange contracts (current) Other accrued liabilities — — 196 — 79 1,262 Total $ 23 $ — $ 7 $ 79

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Mar. 31, 2016
Fair Value Disclosures [Abstract]
Schedule of financial assets measured at fair value on a recurring basis	Our financial assets measured at fair value on a recurring basis consist of the following: March 31, 2016 March 31, 2015 (In millions ) Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Cash Equivalents Money market funds (1) $ 2,413 $ — $ — $ 2,413 $ 2,880 $ — $ — $ 2,880 Time deposits (2) — — — — — 94 — 94 Repurchase agreements (2) — — — — 1,243 — — 1,243 Total cash equivalents $ 2,413 $ — $ — $ 2,413 $ 4,123 $ 94 $ — $ 4,217 (1) Gross unrealized gain and losses were not material for the years ended March 31, 2016 and 2015 based on quoted prices of identical investments. (2) The carrying amounts of these cash equivalents approximated their estimated fair values because of their short maturities.

Lease Obligations (Tables)

Lease Obligations (Tables)	12 Months Ended
	Mar. 31, 2016
Leases, Operating [Abstract]
Schedule of future minimum rental payments for operating leases	At March 31, 2016 , future minimum lease payments required under operating leases that have initial or remaining noncancelable lease terms in excess of one year for years ending March 31 are: (In millions) Noncancelable Operating Leases 2017 $ 363 2018 309 2019 252 2020 209 2021 168 Thereafter 669 Total minimum lease payments (1) $ 1,970 (1) Minimum lease payments have not been reduced by minimum sublease rentals of $45 million due under future noncancelable subleases.

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Mar. 31, 2016
Stockholders' Equity Note [Abstract]
Schedule of shares repurchased over last three years	Information regarding the share repurchase activity over the last three years is as follows: Share Repurchases (1) (In millions, except price per share data) Total Number of Shares Purchased (2) (3) Average Price Paid Per Share Approximate Dollar Value of Shares that May Yet Be Purchased Under the Programs Balance, March 31, 2013 $ 340 Shares repurchased — $ — — Balance, March 31, 2014 $ 340 Shares repurchased 1.5 $ 226.55 (340 ) Balance, March 31, 2015 $ — Shares repurchase plans authorized May 2015 500 October 2015 2,000 Shares repurchased 8.7 $ 173.64 (1,504 ) Balance, March 31, 2016 $ 996 (1) This table does not include shares tendered to satisfy the exercise price in connection with cashless exercises of employee stock options or shares tendered to satisfy tax withholding obligations in connection with employee equity awards. (2) All of the shares purchased were part of the publicly announced programs. (3) The number of shares purchased reflects rounding adjustments.
Schedule of comprehensive income (loss)	Information regarding other comprehensive income (loss) including noncontrolling interests and redeemable noncontrolling interests, net of tax, by component is as follows: Years Ended March 31, (In millions) 2016 2015 2014 Foreign currency translation adjustments (1) Foreign currency translation adjustments arising during period, net of income tax expense (benefit) of ($23), nil and nil (2) (3) $ 113 $ (1,845 ) $ 9 Reclassified to income statement, net of income tax expense of nil, nil and 24 (4) — (10 ) 44 113 (1,855 ) 53 Unrealized gains (losses) on cash flow hedges Unrealized gains (losses) on cash flow hedges arising during period, net of income tax benefit of nil, nil and nil 6 (13 ) (6 ) Reclassified to income statement, net of income tax expense of nil, nil and nil 3 3 — 9 (10 ) (6 ) Changes in retirement-related benefit plans Net actuarial gain (loss) and prior service credit (cost) arising during period, net of income tax expense (benefit) of $13, ($66) and $16 (5) 23 (140 ) 17 Amortization of actuarial loss, prior service cost and transition obligation, net of income tax expense of $18, $6 and $12 (6) 30 11 22 Foreign currency translation adjustments and other, net of income tax expense of nil, nil and nil (3 ) 4 (4 ) Reclassified to income statement, net of income tax expense of nil, nil, and $1 — 1 1 50 (124 ) 36 Other Comprehensive Income (Loss), net of tax $ 172 $ (1,989 ) $ 83 (1) Foreign currency translation adjustments result from the conversion of non-U.S. dollar financial statements of our foreign subsidiaries into the Company’s reporting currency, U.S. dollars, and were primarily related to our foreign subsidiary, Celesio, in 2016 and 2015. (2) The 2016 net foreign currency translation gains of $113 million were primarily due to the recovery of the Euro against the U.S. dollar, partly offset by the weakening of the Canadian dollar and British pound sterling against the U.S. dollar during the period between April 1, 2015 and March 31, 2016. The 2015 foreign currency translation losses of $1,855 million were primarily due to the weakening of the Euro against U.S. dollar during the period between April 1, 2014 and March 31, 2015. (3) 2016 includes net foreign currency translation gains of $16 million and 2015 includes net foreign currency translations losses of $267 million attributable to noncontrolling and redeemable noncontrolling interests. (4) These net foreign currency losses were reclassified from accumulated other comprehensive income (loss) to discontinued operations within our consolidated statement of operations due to the sale of certain businesses. (5) The net gains of $4 million and net losses of $12 million attributable to noncontrolling and redeemable noncontrolling interests in 2016 and 2015. (6) Pre-tax amount was reclassified into cost of sales and operating expenses in the consolidated statements of operations. The related tax expense was reclassified into income tax expense in the consolidated statements of operations.
Schedule of accumulated other comprehensive income (loss)	Information regarding changes in our accumulated other comprehensive income (loss) by component are as follows: (In millions) Foreign Currency Translation Adjustments, Net of Tax Unrealized Losses on Cash Flow Hedges, Net of Tax Unrealized Net Gains (Losses) and Other Components of Benefit Plans, Net of Tax Total Accumulated Other Comprehensive Income (Loss) Balance at March 31, 2014 $ 168 $ (11 ) $ (160 ) $ (3 ) Other comprehensive income (loss) before reclassifications (1,845 ) (13 ) (136 ) (1,994 ) Amounts reclassified to earnings (10 ) 3 12 5 Other comprehensive income (loss) $ (1,855 ) $ (10 ) $ (124 ) $ (1,989 ) Less: amounts attributable to noncontrolling and redeemable interests (267 ) — (12 ) (279 ) Other comprehensive income (loss) attributable to McKesson $ (1,588 ) $ (10 ) $ (112 ) $ (1,710 ) Balance at March 31, 2015 $ (1,420 ) $ (21 ) $ (272 ) $ (1,713 ) Other comprehensive income (loss) before reclassifications 113 6 23 142 Amounts reclassified to earnings and other — 3 27 30 Other comprehensive income (loss) $ 113 $ 9 $ 50 $ 172 Less: amounts attributable to noncontrolling and redeemable interests 16 — 4 20 Other comprehensive income (loss) attributable to McKesson $ 97 $ 9 $ 46 $ 152 Balance at March 31, 2016 $ (1,323 ) $ (12 ) $ (226 ) $ (1,561 )

Segments of Business (Tables)

Segments of Business (Tables)	12 Months Ended
	Mar. 31, 2016
Segment Reporting [Abstract]
Schedule of segment information	Financial information relating to our reportable operating segments and reconciliations to the consolidated totals is as follows: Years Ended March 31, (In millions) 2016 2015 2014 Revenues Distribution Solutions (1) North America pharmaceutical distribution and services $ 158,469 $ 143,711 $ 123,929 International pharmaceutical distribution and services 23,497 26,358 4,485 Medical-Surgical distribution and services 6,033 5,907 5,648 Total Distribution Solutions 187,999 175,976 134,062 Technology Solutions - products and services 2,885 3,069 3,330 Total Revenues $ 190,884 $ 179,045 $ 137,392 Operating profit Distribution Solutions (2) (4) $ 3,553 $ 3,047 $ 2,472 Technology Solutions (3) (4) 519 438 448 Total 4,072 3,485 2,920 Corporate Expenses, Net (4) (469 ) (454 ) (449 ) Interest Expense (353 ) (374 ) (300 ) Income From Continuing Operations Before Income Taxes $ 3,250 $ 2,657 $ 2,171 Depreciation and amortization (5) Distribution Solutions $ 669 $ 750 $ 446 Technology Solutions 107 156 169 Corporate 109 111 120 Total $ 885 $ 1,017 $ 735 Expenditures for long-lived assets (6) Distribution Solutions $ 306 $ 301 $ 179 Technology Solutions 15 27 47 Corporate 167 48 52 Total $ 488 $ 376 $ 278 Revenues, net by geographic area (7) United States $ 158,255 $ 142,810 $ 122,426 Foreign 32,629 36,235 14,966 Total $ 190,884 $ 179,045 $ 137,392 (1) Revenues derived from services represent less than 2% of this segment’s total revenues. (2) Distribution Solutions operating profit for the year ended March 31, 2016, 2015, and 2014 include $244 million , $337 million , and $311 million in pre-tax charges related to our last-in, first-out (“LIFO”) method of accounting for inventories. LIFO expense was less in 2016 primarily due to lower net price increases. For the year ended March 31, 2016 includes $76 million of net cash proceeds representing our share of net settlements of antitrust class action lawsuits as well as a pre-tax gain of $52 million recognized from the sale of our ZEE Medical business. (3) Technology Solutions operating profit for the year ended March 31, 2016 includes a pre-tax gain of $51 million recognized from the sale of our nurse triage business, and for year ended March 31, 2015 includes a non-cash pre-tax charge of $34 million related to the retained workforce business within our International Technology business. (4) During the fourth quarter of 2016, the Company approved the Cost Alignment Plan to reduce its operating expenses and recorded pre-tax restructuring charges of $229 million . Pre-tax charges were recorded as follows: $161 million , $51 million and $17 million within our Distribution Solutions segment, Technology Solutions segment and Corporate. (5) Amounts primarily include amortization of acquired intangible assets purchased in connection with business acquisitions, capitalized software held for sale and capitalized software for internal use. (6) Long-lived assets consist of property, plant and equipment. (7) Net revenues were attributed to geographic areas based on the customers’ shipment locations.
Schedule of segment assets and property, plant and equipment, net by geographic areas	Segment assets and property, plant and equipment, net by geographic areas were as follows: March 31, (In millions) 2016 2015 Segment assets Distribution Solutions $ 47,088 $ 43,982 Technology Solutions 3,072 3,281 Total 50,160 47,263 Corporate Cash and cash equivalents 4,048 5,341 Other 2,355 1,266 Total $ 56,563 $ 53,870 Property, plant and equipment, net United States $ 1,500 $ 1,273 Foreign 778 772 Total $ 2,278 $ 2,045

Quarterly Financial Informati58

Quarterly Financial Information (Unaudited) (Tables)	12 Months Ended
	Mar. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Schedule of quarterly financial information	The quarterly results of operations are not necessarily indicative of the results that may be expected for the entire year. Selected quarterly financial information for the last two years is as follows: (In millions, except per share amounts) First Quarter Second Quarter Third Quarter Fourth Quarter Fiscal 2016 Revenues $ 47,546 $ 48,761 $ 47,899 $ 46,678 Gross profit (1) (2) (3) 2,848 2,844 2,872 2,852 Income after income taxes: Continuing operations (1) (3) (4) $ 599 $ 636 $ 642 $ 465 Discontinued operations (10 ) (6 ) 5 (21 ) Net income $ 589 $ 630 $ 647 $ 444 Net income attributable to McKesson $ 576 $ 617 $ 634 $ 431 Earnings (loss) per common share attributable to McKesson (5) Diluted Continuing operations $ 2.50 $ 2.65 $ 2.71 $ 1.97 Discontinued operations (0.05 ) (0.02 ) 0.02 (0.09 ) Total $ 2.45 $ 2.63 $ 2.73 $ 1.88 Basic Continuing operations $ 2.53 $ 2.68 $ 2.74 $ 1.99 Discontinued operations (0.04 ) (0.02 ) 0.02 (0.09 ) Total $ 2.49 $ 2.66 $ 2.76 $ 1.90 (1) Gross profit for the first, second, third and fourth quarters of 2016 included pre-tax charges related to our last-in-first-out (“LIFO”) method of accounting for inventories of $91 million , $91 million , $33 million and $29 million . (2) Gross profit for the first and third quarters of 2016 included $59 million and $17 million of cash proceeds representing our share of net settlements of antitrust class action lawsuits against drug manufacturers. (3) Financial results for the fourth quarter of 2016 include pre-tax restructuring charges of $229 million within our continuing operations. Charges were recorded as follows: $26 million in cost of sales and $203 million in operating expenses. (4) Financial results for the first quarter of 2016 include an after-tax gain of $38 million from the sale of our nurse triage business, and for the second quarter of 2016 include an after-tax gain of $29 million from the sale of ZEE Medical business. (5) Certain computations may reflect rounding adjustments. (In millions, except per share amounts) First Quarter Second Quarter Third Quarter Fourth Quarter Fiscal 2015 Revenues $ 43,476 $ 44,160 $ 46,484 $ 44,925 Gross profit (1) 2,732 2,864 2,898 2,917 Income after income taxes Continuing operations (1) (2) $ 419 $ 491 $ 521 $ 411 Discontinued operations (3) (8 ) (14 ) (10 ) (267 ) Net income $ 411 $ 477 $ 511 $ 144 Net income attributable to McKesson $ 403 $ 469 $ 472 $ 132 Earnings per common share attributable to McKesson (4) Diluted Continued operations $ 1.76 $ 2.05 $ 2.04 $ 1.69 Discontinued operations (0.04 ) (0.06 ) (0.04 ) (1.13 ) Total $ 1.72 $ 1.99 $ 2.00 $ 0.56 Basic Continuing operations $ 1.79 $ 2.08 $ 2.07 $ 1.72 Discontinued operations (0.04 ) (0.06 ) (0.04 ) (1.15 ) Total $ 1.75 $ 2.02 $ 2.03 $ 0.57 (1) Gross profit for the first, second, third and fourth quarters of 2015 included pre-tax charges related to our LIFO method of accounting for inventories of $98 million , $94 million , $95 million and $50 million . (2) Financial results for the fourth quarter of 2015 included a non-cash after-tax charge of $150 million related to the settlement of controlled substance distribution claims. (3) Discontinued operations for the fourth quarter of 2015 included $235 million non-cash after-tax impairment charges related to our Brazilian pharmaceutical distribution business. (4) Certain computations may reflect rounding adjustments.

Significant Accounting Polici59

Significant Accounting Policies (Details)	12 Months Ended
	Mar. 31, 2016USD ($)customersegment	Mar. 31, 2015USD ($)	Mar. 31, 2014USD ($)	Mar. 31, 2013USD ($)
Accounting Policies [Abstract]
Number of operating segments | segment	2
Restricted cash balance	$ 939,000,000	$ 0
Significant Accounting Policies [Line Items]
LIFO inventory, percentage	74.00%	73.00%
LIFO reserve	$ 1,012,000,000	$ 768,000,000
Charges associated with last-in-first-out inventory method	$ 244,000,000	337,000,000	$ 311,000,000
LIFO inventory, excess of market				$ 60,000,000
LIFO to market adjustment			60,000,000
Capitalized software held for sale, useful life	3 years
Capitalized software held for internal use, net	$ 435,000,000	435,000,000
Capitalized software held for internal use, accumulated amortization	1,130,000,000	1,112,000,000
Sales returns from customers	3,100,000,000	2,700,000,000	1,900,000,000
Supplier reserves	144,000,000	167,000,000
Current net deferred tax liabilities	0	(1,820,000,000)
New Accounting Pronouncement, Early Adoption, Effect
Significant Accounting Policies [Line Items]
Current net deferred tax liabilities	$ 2,000,000,000
Minimum
Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	1 year
Intangible assets, useful life	1 year
Capitalized software held for internal use, useful life	1 year
Maximum
Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	30 years
Intangible assets, useful life	38 years
Capitalized software held for internal use, useful life	10 years
Selling, Distribution and Administrative Expenses
Significant Accounting Policies [Line Items]
Shipping and handling costs	$ 789,000,000	$ 819,000,000	$ 535,000,000
Customer Concentration Risk | Sales Revenue, Net
Significant Accounting Policies [Line Items]
Number of largest customers | customer	10
Percentage of total consolidated revenues	52.40%
Customer Concentration Risk | Sales Revenue, Net | CVS
Significant Accounting Policies [Line Items]
Percentage of total consolidated revenues	20.30%
Customer Concentration Risk | Accounts Receivable
Significant Accounting Policies [Line Items]
Number of largest customers | customer	10
Percentage of total consolidated revenues	32.00%
Customer Concentration Risk | Accounts Receivable | CVS
Significant Accounting Policies [Line Items]
Percentage of total consolidated revenues	18.00%

Business Combinations - Acquisi

Business Combinations - Acquisition of Celesio AG (Details) shares in Millions, $ in Millions	Feb. 06, 2014USD ($)country	Mar. 31, 2014USD ($)shares	Mar. 31, 2016USD ($)	Mar. 31, 2015USD ($)	Mar. 31, 2014USD ($)
Business Acquisition [Line Items]
Cash consideration			$ 40	$ 170	$ 4,634
Goodwill		$ 9,927	$ 9,786	9,817	$ 9,927
Celesio
Business Acquisition [Line Items]
Percentage of outstanding common shares	77.60%
Cash consideration	$ 4,500
Fully diluted common shares (as a percent)	75.60%
Fair value	$ 2,300
Number of countries | country	14
Additional common shares from conversion | shares		20.9
Cash amount from conversion		$ 30
Percentage of outstanding common shares		75.40%			75.40%
Acquired identifiable intangibles				2,300
Fair value of noncontrolling interest				1,505
Goodwill				$ 4,200

Business Combinations - Other A

Business Combinations - Other Acquisition (Details) $ in Millions, CAD in Billions	Apr. 01, 2016USD ($)cancer_treatment_facilitystate	Feb. 29, 2016USD ($)	Mar. 31, 2016USD ($)pharmacy	Dec. 31, 2016USD ($)	Dec. 31, 2016CAD
Sainsbury | United Kingdom
Business Acquisition [Line Items]
Net purchase consideration		$ 174
Interest rate		0.033
UDG
Business Acquisition [Line Items]
Gross purchase consideration			$ 412
Vantage | Subsequent Event
Business Acquisition [Line Items]
Net purchase consideration	$ 527
Number of cancer treatment facilities (more than) | cancer_treatment_facility	51
Number of states | state	13
Biologics | Subsequent Event
Business Acquisition [Line Items]
Gross purchase consideration	$ 700
Rexall Health
Business Acquisition [Line Items]
Currency exchange ratio, CAD per USD			0.77
Rexall Health | Scenario, Forecast
Business Acquisition [Line Items]
Net purchase consideration				$ 2,300	CAD 3
Rexall Health | Canada
Business Acquisition [Line Items]
Number of pharmacies that will be acquired | pharmacy			470

Restructuring - Narrative (Deta

Restructuring - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015
Restructuring Cost and Reserve [Line Items]
Pre-tax charge	$ 229	$ 229
Severance and employee related costs	207
Reserve balance	222	222	$ 0	$ 0
Other Accrued Liabilities
Restructuring Cost and Reserve [Line Items]
Reserve balance	172	172
Other Noncurrent Liabilities
Restructuring Cost and Reserve [Line Items]
Reserve balance	50	50
Reduction in Workforce
Restructuring Cost and Reserve [Line Items]
Severance and employee related costs	117
Business Process Initiatives
Restructuring Cost and Reserve [Line Items]
Severance and employee related costs	90
Minimum
Restructuring Cost and Reserve [Line Items]
Expected total pre-tax charges	270	270
Maximum
Restructuring Cost and Reserve [Line Items]
Expected total pre-tax charges	$ 290	$ 290

Restructuring - Summary of Deta

Restructuring - Summary of Details for Charges Recorded (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2016	Mar. 31, 2014
Restructuring Cost and Reserve [Line Items]
Severance and employee-related costs, net	$ 207
Exit-related costs	5
Asset impairments and accelerated depreciation and amortization	17
Total	229	$ 229
Cost of Sales
Restructuring Cost and Reserve [Line Items]
Total	26
Operating Expenses
Restructuring Cost and Reserve [Line Items]
Total	203
Technology Solutions
Restructuring Cost and Reserve [Line Items]
Severance and employee-related costs, net			$ 7
Operating Segments | Distribution Solutions
Restructuring Cost and Reserve [Line Items]
Severance and employee-related costs, net	147
Exit-related costs	3
Asset impairments and accelerated depreciation and amortization	11
Total	161	161
Operating Segments | Distribution Solutions | Cost of Sales
Restructuring Cost and Reserve [Line Items]
Total	5
Operating Segments | Distribution Solutions | Operating Expenses
Restructuring Cost and Reserve [Line Items]
Total	156
Operating Segments | Technology Solutions
Restructuring Cost and Reserve [Line Items]
Severance and employee-related costs, net	44
Exit-related costs	1
Asset impairments and accelerated depreciation and amortization	6
Total	51	51
Operating Segments | Technology Solutions | Cost of Sales
Restructuring Cost and Reserve [Line Items]
Total	21
Operating Segments | Technology Solutions | Operating Expenses
Restructuring Cost and Reserve [Line Items]
Total	30
Corporate
Restructuring Cost and Reserve [Line Items]
Severance and employee-related costs, net	16
Exit-related costs	1
Asset impairments and accelerated depreciation and amortization	0
Total	17	$ 17
Corporate | Cost of Sales
Restructuring Cost and Reserve [Line Items]
Total	0
Corporate | Operating Expenses
Restructuring Cost and Reserve [Line Items]
Total	$ 17

Restructuring - Summary of Acti

Restructuring - Summary of Activity Related to Restructuring Liability (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2016
2016 Cost Alignment Plan
Beginning balance	$ 0	$ 0
Net restructuring charges recognized	229	229
Non-cash charges	(2)	(2)
Cash Payments	(1)	(1)
Other	(4)	(4)
Ending balance	222	222
Operating Segments | Distribution Solutions
2016 Cost Alignment Plan
Beginning balance	0	0
Net restructuring charges recognized	161	161
Non-cash charges	(4)	(4)
Cash Payments	(1)	(1)
Other	0	0
Ending balance	156	156
Operating Segments | Technology Solutions
2016 Cost Alignment Plan
Beginning balance	0	0
Net restructuring charges recognized	51	51
Non-cash charges	(3)	(3)
Cash Payments	0	0
Other	(3)	(3)
Ending balance	45	45
Corporate
2016 Cost Alignment Plan
Beginning balance	0	0
Net restructuring charges recognized	17	17
Non-cash charges	5	5
Cash Payments	0	0
Other	(1)	(1)
Ending balance	$ 21	$ 21

Asset Impairments and Product65

Asset Impairments and Product Alignment Charges (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2014
Business Combination Segment Allocation [Line Items]
Reduction in force severance charges	$ 207
Technology Solutions
Business Combination Segment Allocation [Line Items]
Nonrecurring charges		$ 57
Product alignment charges		35
Integration related costs		15
Reduction in force severance charges		7
Asset impairment charges		15
Technology Solutions | Cost of Sales
Business Combination Segment Allocation [Line Items]
Nonrecurring charges		34
Technology Solutions | Operating Expenses
Business Combination Segment Allocation [Line Items]
Nonrecurring charges		23
Technology Solutions | Severance Charges Due to Reorganization
Business Combination Segment Allocation [Line Items]
Reduction in force severance charges		$ 35

Divestiture of Businesses (Deta

Divestiture of Businesses (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Discontinued Operations Disclosures
Gain from sale of business, pre-tax			$ 103	$ 0	$ 0
Distribution Solutions | ZEE Medical Business | Operating Segments
Discontinued Operations Disclosures
Proceeds from divestiture of businesses	$ 134
Gain from sale of business, pre-tax	52		52
Gain from sale of business, after tax	$ 29
Technology Solutions | Nurse Triage | Operating Segments
Discontinued Operations Disclosures
Proceeds from divestiture of businesses		$ 84
Gain from sale of business, pre-tax		51	$ 51
Gain from sale of business, after tax		$ 38

Share-Based Compensation - Comp

Share-Based Compensation - Components of Share-Based Compensation Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 123	$ 174	$ 160
Tax benefit for share-based compensation expense	(41)	(61)	(55)
Share-based compensation expense, net of tax	82	113	105
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	88	137	126
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	22	24	22
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 13	$ 13	$ 12

Share-Based Compensation - Narr

Share-Based Compensation - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Jul. 31, 2013
Share-based Compensation [Abstract]
Non-cash credits	$ 14
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vested and exercisable (in shares)	2,000,000
Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vested and exercisable (in shares)	146,000
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock award contractual term	7 years
Stock award vesting period	4 years
RSUs | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock award vesting period	3 years
RSUs | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock award vesting period	4 years
PeRSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock award vesting period	4 years
TSRUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock award vesting period	3 years
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	21,000,000
Number of shares available for grant	4,000,000
Period over which payroll is deducted to purchase shares	3 months
Percentage of market price for share purchase	85.00%
Percentage of market price deduction for share purchases	15.00%
2013 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized		30,000,000
Number of shares available for grant	29,000,000

Share-Based Compensation - Sche

Share-Based Compensation - Schedule of Assumptions for Stock Options Fair Values (Details) - Stock Option	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected stock price volatility (as a percent)	21.00%	22.00%	22.00%
Expected dividend yield (as a percent)	0.40%	0.60%	0.70%
Risk-free interest rate	1.40%	1.30%	0.70%
Expected life (in years)	4 years	4 years	4 years

Share-Based Compensation - Summ

Share-Based Compensation - Summary of Options Outstanding (Details) shares in Millions	12 Months Ended
	Mar. 31, 2016$ / sharesshares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of Options Outstanding at Year End (in shares) | shares	4
Number of Options Exercisable at Year End (in shares) | shares	2
Range One
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices lower limit (in dollars per share)	$ 40.46
Range of exercise prices upper limit (in dollars per share)	$ 140.19
Number of Options Outstanding at Year End (in shares) | shares	3
Weighted- Average Remaining Contractual Life (Years)	2 years
Weighted- Average Exercise Price (in dollars per share)	$ 83.62
Number of Options Exercisable at Year End (in shares) | shares	2
Weighted- Average Exercise Price (in dollars per share)	$ 78.01
Range Two
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices lower limit (in dollars per share)	140.20
Range of exercise prices upper limit (in dollars per share)	$ 239.93
Number of Options Outstanding at Year End (in shares) | shares	1
Weighted- Average Remaining Contractual Life (Years)	6 years
Weighted- Average Exercise Price (in dollars per share)	$ 206.58
Number of Options Exercisable at Year End (in shares) | shares	0
Weighted- Average Exercise Price (in dollars per share)	$ 180.24

Share-Based Compensation - Sc71

Share-Based Compensation - Schedule of Stock Option Activity (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Shares
Beginning balance (in shares)	5
Granted (in shares)	1
Cancelled (in shares)	(1)
Exercised (in shares)	(1)
Ending balance (in shares)	4	5
Weighted- Average Exercise Price
Beginning balance (in dollars per share)	$ 95.01
Granted (in dollars per share)	236.77
Cancelled (in dollars per share)	149.19
Exercised (in dollars per share)	63.75
Ending balance (in dollars per share)	$ 118.95	$ 95.01
Weighted- Average Remaining Contractual Term (Years)
Stock options outstanding, remaining contractual term	3 years	4 years
Stock options outstanding, aggregate intrinsic value	$ 201	$ 539
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract]
Stock options vested and expected to vest (in shares)	3
Stock options vested and exercisable (in shares)	2
Stock options vested and expected to vest, weighted average exercise price (in dollars per share)	$ 118.21
Stock options vested and exercisable, weighted average exercise price (in dollars per share)	$ 85.15
Stock options vested and expected to vest, weighted average remaining contractual term	3 years
Stock options vested and exercisable, weighted average remaining contractual term	2 years
Stock options vested and expected to vest, aggregate intrinsic value	$ 200
Stock options vested and exercisable, aggregate intrinsic value	$ 173

Share-Based Compensation - Sc72

Share-Based Compensation - Schedule of Data Related to Stock Option Activity (Details) - Stock Option - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value per stock option (in dollars per share)	$ 44.04	$ 35.49	$ 21.45
Aggregate intrinsic value on exercise	$ 107	$ 153	$ 144
Cash received upon exercise	47	76	111
Tax benefits realized related to exercise	42	60	55
Total fair value of stock options vested	18	20	24
Total compensation cost, net of estimated forfeitures, related to unvested stock options not yet recognized, pre-tax	$ 20	$ 22	$ 29
Weighted-average period in years over which stock option compensation cost is expected to be recognized	2 years	2 years	1 year

Share-Based Compensation - Sc73

Share-Based Compensation - Schedule of Weighted-Average Assumptions Used to Estimate Fair Value of TSRUs (Details) - TSRUs	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected stock price volatility (as a percent)	18.00%	21.00%
Expected dividend yield (as a percent)	0.40%	0.50%
Risk-free interest rate	0.90%	0.70%
Expected life (in years)	3 years	3 years

Share-Based Compensation - Sc74

Share-Based Compensation - Schedule of Restricted Stock Unit Award Activity (Details) - Restricted stock units shares in Millions	12 Months Ended
	Mar. 31, 2016$ / sharesshares
Shares
Beginning balance (in shares) | shares	4
Granted (in shares) | shares	1
Cancelled (in shares) | shares	(1)
Vested (in shares) | shares	(1)
Ending balance (in shares) | shares	3
Weighted- Average Grant Date Fair Value Per Share
Beginning balance (in dollars per shares) | $ / shares	$ 129.57
Granted (in dollars per share) | $ / shares	240.35
Cancelled (in dollars per share) | $ / shares	159.17
Vested (in dollars per share) | $ / shares	89.44
Ending balance (in dollars per shares) | $ / shares	$ 176.59

Share-Based Compensation - Su75

Share-Based Compensation - Summary of Data Related to RSU Activity (Details) - Restricted stock units - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of shares vested	$ 104	$ 126	$ 184
Total compensation cost, net of estimated forfeitures, related to nonvested restricted stock unit awards not yet recognized, pre-tax	$ 144	$ 206	$ 236
Weighted-average period in years over which restricted stock unit award cost is expected to be recognized	2 years	2 years	2 years

Other Income, Net (Details)

Other Income, Net (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Other Nonoperating Income (Expense) [Abstract]
Interest income	$ 18	$ 20	$ 16
Equity in earnings, net	15	12	0
Other, net	25	31	16
Total	$ 58	$ 63	$ 32

Income Taxes - Schedule of Inco

Income Taxes - Schedule of Income from Continuing Operations Before Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Income from continuing operations before income taxes
U.S.	$ 2,319	$ 1,893	$ 1,554
Foreign	931	764	617
Income from Continuing Operations Before Income Taxes	$ 3,250	$ 2,657	$ 2,171

Income Taxes - Components Of Pr

Income Taxes - Components Of Provision For Income Taxes Related To Continuing Operations (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Current
Federal	$ 658	$ 453	$ 484
State	96	90	64
Foreign	90	101	193
Total current	844	644	741
Deferred
Federal	95	195	24
State	42	53	10
Foreign	(73)	(77)	(18)
Total deferred	64	171	16
Income tax expense	$ 908	$ 815	$ 757

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($)	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Income Tax Contingency [Line Items]
Income tax expense	$ 908,000,000	$ 815,000,000	$ 757,000,000
Net discrete tax expense (benefit)	$ (42,000,000)	$ (33,000,000)	$ 94,000,000
Income tax rates	27.90%	30.70%	34.90%
Undistributed earnings of foreign operations	$ 5,831,000,000
Deferred tax liability	0
Valuation allowance	267,000,000	$ 229,000,000
Increase in valuation allowance	38,000,000
Unrecognized tax benefits	555,000,000	616,000,000	$ 647,000,000	$ 560,000,000
Unrecognized tax benefits that would Impact income tax expense and the effective tax rate	380,000,000
Potential reduction of unrecognized benefits due to audit resolutions and expiration of statutes of limitations (up to)	125,000,000
Income tax expense (benefit), before any tax effect, related to accrued interest and penalties	12,000,000	(24,000,000)	48,000,000
Accrued interest and penalties on unrecognized tax benefits	77,000,000	122,000,000
Foreign Tax Authority
Income Tax Contingency [Line Items]
Net discrete tax expense (benefit)	(19,000,000)
Federal, state and foreign net operating loss carryforwards	889,000,000
Tax Reserve
Income Tax Contingency [Line Items]
Net discrete tax expense (benefit)	(25,000,000)
IRS
Income Tax Contingency [Line Items]
Net discrete tax expense (benefit)		$ (55,000,000)
Canada Revenue Agency
Income Tax Contingency [Line Items]
Net discrete tax expense (benefit)	(8,000,000)		$ 122,000,000
Federal
Income Tax Contingency [Line Items]
Federal, state and foreign net operating loss carryforwards	35,000,000
State
Income Tax Contingency [Line Items]
Federal, state and foreign net operating loss carryforwards	$ 1,790,000,000

Income Taxes - Reconciliation B

Income Taxes - Reconciliation Between Effective Tax Rate On Income From Continuing Operations And Statutory Tax Rate (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Income Tax Disclosure [Abstract]
Income tax expense at federal statutory rate	$ 1,137	$ 930	$ 760
State income taxes net of federal tax benefit	92	81	57
Foreign income taxed at various rates	(295)	(247)	(177)
Canadian litigation	(8)	0	122
Controlled substance distribution reserve	0	58	0
Unrecognized tax benefits and settlements	(6)	10	(6)
Tax credits	(18)	(10)	(6)
Other, net	6	(7)	7
Income tax expense	$ 908	$ 815	$ 757

Income Taxes - Components Of De

Income Taxes - Components Of Deferred Tax Balances (Details) - USD ($) $ in Millions	Mar. 31, 2016	Mar. 31, 2015
Assets
Receivable allowances	$ 110	$ 83
Deferred revenue	77	72
Compensation and benefit related accruals	710	681
Net operating loss and credit carryforwards	367	316
Other	275	266
Subtotal	1,539	1,418
Less: valuation allowance	(267)	(229)
Total assets	1,272	1,189
Liabilities
Inventory valuation and other assets	(2,619)	(2,333)
Fixed assets and systems development costs	(326)	(324)
Intangibles	(981)	(1,073)
Other	(21)	(61)
Total liabilities	(3,947)	(3,791)
Net deferred tax liability	(2,675)	(2,602)
Current net deferred tax asset	0	27
Current net deferred tax liability	0	(1,820)
Long-term deferred tax asset	59	50
Long-term deferred tax liability	$ (2,734)	$ (859)

Income Taxes - Gross Unrecogniz

Income Taxes - Gross Unrecognized Tax Benefits (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits at beginning of period	$ 616	$ 647	$ 560
Additions based on tax positions related to prior years	116	62	106
Reductions based on tax positions related to prior years	(62)	(18)	(23)
Additions based on tax positions related to current year	28	27	23
Reductions based on settlements	(141)	(65)	(4)
Reductions based on the lapse of the applicable statutes of limitations	(6)	(12)	(7)
Exchange rate fluctuations	4	(25)	(8)
Unrecognized tax benefits at end of period	$ 555	$ 616	$ 647

Discontinued Operations - Narra

Discontinued Operations - Narrative (Details) - USD ($) $ in Millions	3 Months Ended				12 Months Ended
	Mar. 31, 2015	Sep. 30, 2014	Jun. 30, 2014	Dec. 31, 2013	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Discontinued Operations Disclosures
Pre-tax loss					$ 0	$ 6	$ 5
Brazil Distribution Business
Discontinued Operations Disclosures
Pre tax impairment charges	$ 241
Impairment charges, after tax	235
Reduction in carrying value of property, plant and equipment, other long-lived assets and goodwill	31
Remaining difference between fair value and carrying value	210
Cumulative foreign currency translation losses	$ 17					$ 17
Brazil Distribution Business | Minimum
Discontinued Operations Disclosures
Minimum expected amount of impairment charge, after-tax					80
Brazil Distribution Business | Maximum
Discontinued Operations Disclosures
Minimum expected amount of impairment charge, after-tax					$ 100
Hospital Automation Business
Discontinued Operations Disclosures
Pre-tax loss				$ 5
After-tax loss				7
International Technology, Workforce | Cost of Sales
Discontinued Operations Disclosures
Non-cash pre-tax charge			$ 34
Non-cash after-tax charge			$ 27
International Technology, Software
Discontinued Operations Disclosures
Pre-tax loss		$ 6
After-tax loss		$ 6
International Technology
Discontinued Operations Disclosures
Pre tax impairment charges				80
Impairment charges, after tax				$ 80

Discontinued Operations - Sched

Discontinued Operations - Schedule of Results from Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Discontinued Operations and Disposal Groups [Abstract]
Revenues									$ 1,603	$ 2,196	$ 637
Loss from discontinued operations									(24)	(321)	(177)
Loss on sale									0	(6)	(5)
Loss from discontinued operations before income tax									(24)	(327)	(182)
Income tax (expense) benefit									(8)	28	26
Loss from discontinued operations, net of tax	$ (21)	$ 5	$ (6)	$ (10)	$ (267)	$ (10)	$ (14)	$ (8)	$ (32)	$ (299)	$ (156)

Discontinued Operations - Summa

Discontinued Operations - Summary of Carrying Amounts of Major Classes of Assets and Liabilities (Details) - Discontinued Operations, Held-for-sale or Disposed of by Sale - USD ($) $ in Millions	Mar. 31, 2016	Mar. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Receivables, net	$ 289	$ 314
Inventories, net	266	254
Other assets	80	92
Total assets of discontinued operations	635	660
Drafts and account payable	264	209
Short-term borrowings	142	126
Other liabilities	254	328
Total liabilities of discontinued operations	$ 660	$ 663

Noncontrolling Interests and 86

Noncontrolling Interests and Redeemable Noncontrolling Interests - Narrative (Details) shares in Millions	1 Months Ended		9 Months Ended	12 Months Ended
	Jul. 31, 2014USD ($)	Apr. 30, 2014USD ($)shares	Dec. 31, 2015	Mar. 31, 2016USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2014USD ($)€ / shares	Dec. 02, 2014€ / shares
Noncontrolling Interest [Line Items]
Put right value, exercise period			2 months	2 months
Noncontrolling Interest
Noncontrolling Interest [Line Items]
Decrease in noncontrolling interest					$ 60,000,000
Celesio
Noncontrolling Interest [Line Items]
Annual recurring compensation (in euro per share) | € / shares							€ 0.83
Dividends paid (in euro per share) | € / shares						€ 0.83
Put right (in dollars per share) | € / shares							€ 22.99
Percentage points							5.00%
Total attribution of net income to the noncontrolling shareholders				$ 44,000,000	62,000,000
Carrying value of noncontrolling interests				1,410,000,000	1,390,000,000	€ 1,500,000,000
Maximum redemption value				$ 1,280,000,000	$ 1,210,000,000
Percentage of outstanding common shares				76.00%	76.00%
Celesio | Redeemable Noncontrolling Interests
Noncontrolling Interest [Line Items]
Guaranteed dividend amount					$ 50,000,000
Recurring compensation				$ 44,000,000	12,000,000
Decrease in noncontrolling interest					9,000,000
Celesio | Noncontrolling Interest
Noncontrolling Interest [Line Items]
Decrease in noncontrolling interest	$ 25,000,000	$ 35,000,000
Additional purchase of shares | shares		1
Net foreign currency translation losses attributable to noncontrolling interest					$ 138,000,000

Noncontrolling Interests and 87

Noncontrolling Interests and Redeemable Noncontrolling Interests - Schedule of Changes in Noncontrolling Interests and Redeemable Noncontrolling Interest (Details) - USD ($) $ in Millions	1 Months Ended		12 Months Ended
	Jul. 31, 2014	Apr. 30, 2014	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance			$ 84
Net income attributable to noncontrolling interests			52	$ 67	$ (5)
Ending balance			84	84
Noncontrolling interests
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance		$ 1,796	84	1,796
Net income attributable to noncontrolling interests			8	5
Other comprehensive loss			0	(174)
Purchase of noncontrolling interests				(60)
Reclassification from Total Equity to Redeemable Noncontrolling Interests (5)				(1,500)
Reclassification of guaranteed dividends and recurring compensation to other accrued liabilities			0	0
Other			(8)	17
Ending balance			84	84	1,796
Celesio | Noncontrolling interests
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Purchase of noncontrolling interests	$ (25)	(35)
Celesio | Redeemable Noncontrolling Interests
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance		$ 0	1,386	0
Net income attributable to noncontrolling interests			44	62
Other comprehensive loss			20	(105)
Purchase of noncontrolling interests				(9)
Reclassification from Total Equity to Redeemable Noncontrolling Interests (5)				1,500
Reclassification of guaranteed dividends and recurring compensation to other accrued liabilities			(44)	(62)
Other			0	0
Ending balance			$ 1,406	$ 1,386	$ 0

Earnings Per Common Share - Sch

Earnings Per Common Share - Schedule of Basic and Diluted Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended								12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share [Abstract]
Income from continuing operations	$ 465	$ 642	$ 636	$ 599	$ 411	$ 521	$ 491	$ 419	$ 2,342	$ 1,842	$ 1,414
Net (income) loss attributable to noncontrolling interests									(52)	(67)	5
Income from continuing operations attributable to McKesson									2,290	1,775	1,419
Loss from discontinued operations, net of tax	(21)	5	(6)	(10)	(267)	(10)	(14)	(8)	(32)	(299)	(156)
Net Income Attributable to McKesson Corporation	$ 431	$ 634	$ 617	$ 576	$ 132	$ 472	$ 469	$ 403	$ 2,258	$ 1,476	$ 1,263
Weighted average common shares outstanding:
Basic (in shares)									230	232	229
Earnings Per Share, Basic and Diluted, by Common Class [Line Items]
Diluted (in shares)									233	235	233
Diluted
Continuing operations (in dollars per share)	$ 1.97	$ 2.71	$ 2.65	$ 2.50	$ 1.69	$ 2.04	$ 2.05	$ 1.76	$ 9.84	$ 7.54	$ 6.08
Discontinued operations (in dollars per share)	(0.09)	0.02	(0.02)	(0.05)	(1.13)	(0.04)	(0.06)	(0.04)	(0.14)	(1.27)	(0.67)
Total (in dollars per share)	1.88	2.73	2.63	2.45	0.56	2	1.99	1.72	9.70	6.27	5.41
Basic
Continuing operations (in dollars per share)	1.99	2.74	2.68	2.53	1.72	2.07	2.08	1.79	9.96	7.66	6.19
Discontinued operations (in dollars per share)	(0.09)	0.02	(0.02)	(0.04)	(1.15)	(0.04)	(0.06)	(0.04)	(0.14)	(1.29)	(0.68)
Total (in dollars per share)	$ 1.90	$ 2.76	$ 2.66	$ 2.49	$ 0.57	$ 2.03	$ 2.02	$ 1.75	$ 9.82	$ 6.37	$ 5.51
Stock Option
Earnings Per Share, Basic and Diluted, by Common Class [Line Items]
Effect of dilutive securities (in shares)									1	1	1
Restricted stock units
Earnings Per Share, Basic and Diluted, by Common Class [Line Items]
Effect of dilutive securities (in shares)									2	2	3

Earnings Per Common Share - Nar

Earnings Per Common Share - Narrative (Details) - shares shares in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share [Abstract]
Potentially dilutive shares excluded from diluted earnings per share	2	1	2

Receivables, Net (Details)

Receivables, Net (Details) - USD ($) $ in Millions	Mar. 31, 2016	Mar. 31, 2015
Receivables, Net, Current [Abstract]
Customer accounts	$ 14,519	$ 13,117
Other	3,711	2,965
Total	18,230	16,082
Allowances	(250)	(168)
Net	$ 17,980	$ 15,914

Property, Plant and Equipment91

Property, Plant and Equipment, Net (Details) - USD ($) $ in Millions	Mar. 31, 2016	Mar. 31, 2015
Property, Plant and Equipment, Net [Abstract]
Land	$ 228	$ 207
Building, machinery, equipment and other	3,556	3,237
Total property, plant and equipment	3,784	3,444
Accumulated depreciation	(1,506)	(1,399)
Property, plant and equipment, net	$ 2,278	$ 2,045

Goodwill and Intangible Asset92

Goodwill and Intangible Assets, Net - Schedule of Changes in the Carrying Amount of Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 9,817	$ 9,927
Goodwill acquired	21	93
Amount reclassified to assets held-for-sale		(15)
Acquisition accounting, transfers and other adjustments	8	625
Goodwill disposed	(86)
Foreign currency translation adjustments, net	26	(813)
Goodwill, ending balance	9,786	9,817
Distribution Solutions
Goodwill [Roll Forward]
Goodwill, beginning balance	7,994	8,078
Goodwill acquired	21	93
Amount reclassified to assets held-for-sale		(14)
Acquisition accounting, transfers and other adjustments	8	625
Goodwill disposed	(59)
Foreign currency translation adjustments, net	23	(788)
Goodwill, ending balance	7,987	7,994
Technology Solutions
Goodwill [Roll Forward]
Goodwill, beginning balance	1,823	1,849
Goodwill acquired	0	0
Amount reclassified to assets held-for-sale		(1)
Acquisition accounting, transfers and other adjustments	0	0
Goodwill disposed	(27)
Foreign currency translation adjustments, net	3	(25)
Goodwill, ending balance	$ 1,799	$ 1,823

Goodwill and Intangible Asset93

Goodwill and Intangible Assets, Net - Goodwill Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2016	Mar. 31, 2015
Technology Solutions
Goodwill [Line Items]
Accumulated goodwill impairment loss	$ 36	$ 36

Goodwill and Intangible Asset94

Goodwill and Intangible Assets, Net - Schedule of Information Regarding Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 5,140	$ 5,204
Accumulated Amortization	(2,119)	(1,763)
Net Carrying Amount	$ 3,021	3,441
Customer lists
Finite-Lived Intangible Assets [Line Items]
Weighted Average Remaining Amortization Period (Years)	7 years
Gross Carrying Amount	$ 2,652	2,683
Accumulated Amortization	(1,324)	(1,116)
Net Carrying Amount	$ 1,328	1,567
Service agreements
Finite-Lived Intangible Assets [Line Items]
Weighted Average Remaining Amortization Period (Years)	14 years
Gross Carrying Amount	$ 959	957
Accumulated Amortization	(269)	(215)
Net Carrying Amount	$ 690	742
Pharmacy licenses
Finite-Lived Intangible Assets [Line Items]
Weighted Average Remaining Amortization Period (Years)	25 years
Gross Carrying Amount	$ 857	874
Accumulated Amortization	(121)	(65)
Net Carrying Amount	$ 736	809
Trademarks and trade names
Finite-Lived Intangible Assets [Line Items]
Weighted Average Remaining Amortization Period (Years)	14 years
Gross Carrying Amount	$ 314	315
Accumulated Amortization	(96)	(82)
Net Carrying Amount	$ 218	233
Technology
Finite-Lived Intangible Assets [Line Items]
Weighted Average Remaining Amortization Period (Years)	2 years
Gross Carrying Amount	$ 195	213
Accumulated Amortization	(182)	(184)
Net Carrying Amount	$ 13	29
Other
Finite-Lived Intangible Assets [Line Items]
Weighted Average Remaining Amortization Period (Years)	3 years
Gross Carrying Amount	$ 163	162
Accumulated Amortization	(127)	(101)
Net Carrying Amount	$ 36	$ 61

Goodwill and Intangible Asset95

Goodwill and Intangible Assets, Net - Intangible Assets Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization expense of intangible assets	$ 431	$ 494	$ 319
Estimated annual amortization expense, 2017	355
Estimated annual amortization expense, 2018	337
Estimated annual amortization expense, 2019	308
Estimated annual amortization expense, 2020	281
Estimated annual amortization expense, 2021	262
Estimated annual amortization expense, after 2021	$ 1,478

Capitalized Software Held for96

Capitalized Software Held for Sale, Net (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Movement in Capitalized Computer Software, Net [Roll Forward]
Beginning balance	$ 91	$ 103	$ 126
Amounts capitalized	30	34	40
Amortization expense	(37)	(40)	(50)
Impairment charges	0	0	(12)
Disposal	(5)	0	0
Foreign currency translations adjustments, net	(1)	(6)	(1)
Ending balance	$ 78	$ 91	$ 103

Debt and Financing Activities -

Debt and Financing Activities - Schedule Of Long-Term Debt (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 05, 2014
Debt Instrument [Line Items]
Total debt	$ 8,147	$ 9,709
Less current portion	(1,612)	(1,529)
Total long-term debt	6,535	8,180
Floating Rate Notes due September 10, 2015
Debt Instrument [Line Items]
Total debt	$ 0	400
Debt maturity date	Sep. 10, 2015
0.95% Notes due December 4, 2015
Debt Instrument [Line Items]
Total debt	$ 0	500
Debt interest rate	0.95%
Debt maturity date	Dec. 4, 2015
3.25% Notes due March 1, 2016
Debt Instrument [Line Items]
Total debt	$ 0	600
Debt interest rate	3.25%
Debt maturity date	Mar. 1, 2016
5.70% Notes due March 1, 2017
Debt Instrument [Line Items]
Total debt	$ 500	500
Debt interest rate	5.70%
Debt maturity date	Mar. 1, 2017
1.29% Notes due March 10, 2017
Debt Instrument [Line Items]
Total debt	$ 700	700
Debt interest rate	1.29%		1.29%
Debt maturity date	Mar. 10, 2017
1.40% Notes due March 15, 2018
Debt Instrument [Line Items]
Total debt	$ 500	499
Debt interest rate	1.40%
Debt maturity date	Mar. 15, 2018
7.50% Notes due February 15, 2019
Debt Instrument [Line Items]
Total debt	$ 350	349
Debt interest rate	7.50%
Debt maturity date	Feb. 15, 2019
2.28% Notes due March 15, 2019
Debt Instrument [Line Items]
Total debt	$ 1,100	1,100
Debt interest rate	2.28%		2.28%
Debt maturity date	Mar. 15, 2019
4.75% Notes due March 1, 2021
Debt Instrument [Line Items]
Total debt	$ 599	599
Debt interest rate	4.75%
Debt maturity date	Mar. 1, 2021
2.70% Notes due December 15, 2022
Debt Instrument [Line Items]
Total debt	$ 400	400
Debt interest rate	2.70%
Debt maturity date	Dec. 15, 2022
2.85% Notes due March 15, 2023
Debt Instrument [Line Items]
Total debt	$ 400	400
Debt interest rate	2.85%
Debt maturity date	Mar. 15, 2023
3.80% Notes due March 15, 2024
Debt Instrument [Line Items]
Total debt	$ 1,100	1,100
Debt interest rate	3.80%		3.80%
Debt maturity date	Mar. 15, 2024
7.65% Debentures due March 1, 2027
Debt Instrument [Line Items]
Total debt	$ 175	175
Debt interest rate	7.65%
Debt maturity date	Mar. 1, 2027
6.00% Notes due March 1, 2041
Debt Instrument [Line Items]
Total debt	$ 493	493
Debt interest rate	6.00%
Debt maturity date	Mar. 1, 2041
4.88% Notes due March 15, 2044
Debt Instrument [Line Items]
Total debt	$ 800	800
Debt interest rate	4.88%		4.88%
Debt maturity date	Mar. 15, 2044
4.00% Bonds due October 18, 2016
Debt Instrument [Line Items]
Total debt	$ 403	388
Debt interest rate	4.00%
Debt maturity date	Oct. 18, 2016
4.50% Bonds due April 26, 2017
Debt Instrument [Line Items]
Total debt	$ 583	563
Debt interest rate	4.50%
Debt maturity date	Apr. 26, 2017
Lease and other obligations
Debt Instrument [Line Items]
Total debt	$ 44	$ 143

Debt and Financing Activities98

Debt and Financing Activities - Long-Term Debt (Details) - USD ($)	Mar. 05, 2014	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Debt Instrument [Line Items]
Total debt outstanding		$ 8,147,000,000	$ 9,709,000,000
Net proceeds from issuance of notes	$ 4,068,000,000	$ 0	3,000,000	$ 4,124,000,000
Days notice for redemption prior to maturity		30 days
Redemption purchase offer		101.00%
Floating Rate Notes
Debt Instrument [Line Items]
Total debt outstanding		$ 0	400,000,000
Aggregate principal amount	400,000,000
2017 Notes
Debt Instrument [Line Items]
Total debt outstanding		$ 700,000,000	700,000,000
Aggregate principal amount	$ 700,000,000
Debt interest rate	1.29%	1.29%
2019 Notes
Debt Instrument [Line Items]
Total debt outstanding		$ 1,100,000,000	1,100,000,000
Aggregate principal amount	$ 1,100,000,000
Debt interest rate	2.28%	2.28%
2024 Notes
Debt Instrument [Line Items]
Total debt outstanding		$ 1,100,000,000	1,100,000,000
Aggregate principal amount	$ 1,100,000,000
Debt interest rate	3.80%	3.80%
2044 Notes
Debt Instrument [Line Items]
Total debt outstanding		$ 800,000,000	800,000,000
Aggregate principal amount	$ 800,000,000
Debt interest rate	4.88%	4.88%
Long-term Debt, Current Maturities
Debt Instrument [Line Items]
Total debt outstanding		$ 1,612,000,000	$ 1,529,000,000

Debt and Financing Activities99

Debt and Financing Activities - Senior Bridge Term Loan Facilities (Details) - 2014 Bridge Loan - USD ($)	Mar. 10, 2014	Feb. 04, 2014	Jan. 31, 2014	Mar. 11, 2014	Mar. 31, 2014
Debt Instrument [Line Items]
Credit facility borrowing capacity			$ 5,500,000,000
Credit facility expiration period			364 days
Amount borrowed under facility		$ 4,957,000,000
Repayments of lines of credit	$ 4,076,000,000
Fees related to bridge loan					$ 46,000,000
London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Credit facility interest rate				1.39%

Debt and Financing Activitie100

Debt and Financing Activities - Other Information (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Debt Instrument [Line Items]
Future principal payments of long-term debt in 2017	$ 1,612
Future principal payments of long-term debt in 2018	1,092
Future principal payments of long-term debt in 2019	1,458
Future principal payments of long-term debt in 2020	3
Future principal payments of long-term debt in 2021	2
Future principal payments of long-term debt, thereafter	3,980
Repayments of loan	1,598	$ 353	$ 348
Total debt outstanding	8,147	9,709
Floating Rate Notes
Debt Instrument [Line Items]
Repayments of loan	400
Total debt outstanding	0	$ 400
6.50% Notes Due February 15 2014
Debt Instrument [Line Items]
Repayments of loan			$ 350
Debt interest rate			6.50%
0.95% Notes Due December 4 2015
Debt Instrument [Line Items]
Repayments of loan	$ 500
Debt interest rate	0.95%
3.25% Notes Due March 1 2016
Debt Instrument [Line Items]
Repayments of loan	$ 600
Debt interest rate	3.25%

Debt and Financing Activitie101

Debt and Financing Activities - Revolving Credit Facilities (Details)	3 Months Ended	12 Months Ended
	Dec. 31, 2015USD ($)	Mar. 31, 2016USD ($)	Mar. 31, 2015USD ($)	Mar. 31, 2014USD ($)	Mar. 31, 2013USD ($)	Mar. 31, 2012USD ($)	Oct. 31, 2015USD ($)	Mar. 31, 2015EUR (€)
Global Facility
Line of Credit Facility [Line Items]
Credit facility borrowing capacity	$ 3,500,000,000						$ 3,500,000,000
Revolving credit facility term	5 years
Aggregate sublimit	$ 3,150,000,000
Credit facility outstanding, long-term		$ 0
Debt to capital ratio		0.65
Revolving Credit Facility
Line of Credit Facility [Line Items]
Credit facility borrowing capacity							$ 1,300,000,000	€ 500,000,000
Revolving credit facility term			5 years
Amount borrowed under facility			$ 0	$ 0	$ 0	$ 0
Line of Credit
Line of Credit Facility [Line Items]
Credit facility borrowing capacity		$ 427,000,000
Bilateral Lines of Credit
Line of Credit Facility [Line Items]
Amount borrowed under facility		$ 641,000,000	225,000,000
Interest rate, minimum		0.18%
Interest rate, maximum		6.00%
Repayments of lines of credit		$ 635,000,000	267,000,000
Outstanding amount under credit lines		$ 28,000,000	$ 29,000,000

Debt and Financing Activitie102

Debt and Financing Activities - Account Receivable Facilities (Details) - USD ($)	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2015
AR Facility
Debt Instrument [Line Items]
Credit facility borrowing capacity				$ 1,350,000,000
Borrowings outstanding	$ 0	$ 0
Pledged Assets, Not Separately Reported, Finance Receivables		0
Amount borrowed under facility			$ 550,000,000
Repayments of lines of credit			550,000,000
Factoring Facilities
Debt Instrument [Line Items]
Borrowings outstanding	7,000,000	135,000,000
Amount borrowed under facility	919,000,000	2,875,000,000	570,000,000
Repayments of lines of credit	$ 1,055,000,000	$ 2,908,000,000	$ 575,000,000
Factoring Facilities | Minimum
Debt Instrument [Line Items]
Debt interest rate	0.85%
Factoring Facilities | Maximum
Debt Instrument [Line Items]
Debt interest rate	1.26%

Debt and Financing Activitie103

Debt and Financing Activities - Commercial Paper (Details) - USD ($)	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014	Nov. 30, 2015
Debt Instrument [Line Items]
Commercial paper issuances	$ 0	$ 0	$ 0
Commercial paper outstanding	$ 0
Commercial Paper
Debt Instrument [Line Items]
Credit facility borrowing capacity (up to)				$ 3,500,000,000

Variable Interest Entities (Det

Variable Interest Entities (Details) - USD ($) $ in Millions	Mar. 31, 2016	Mar. 31, 2015
Variable Interest Entity, Not Primary Beneficiary, Disclosures [Abstract]
VIE consolidated assets	$ 119	$ 144
VIE consolidated liabilities	44	51
Unconsolidated VIE maximum exposure to loss	$ 1,100	$ 1,200

Pension Benefits - Narrative (D

Pension Benefits - Narrative (Details)	Dec. 31, 1996	Mar. 31, 2016USD ($)$ / shares	Mar. 31, 2015USD ($)	Mar. 31, 2014USD ($)
Defined Benefit Plan Disclosure [Line Items]
Expected amortization of actuarial loss		$ 15,000,000
Prior service credit		1,000,000
Actuarial loss		47,000,000
Expected benefit payments in 2017		59,000,000
Expected benefit payments in 2018		174,000,000
Expected benefit payments in 2019		110,000,000
Expected benefit payments in 2020		66,000,000
Expected benefit payments in 2021		65,000,000
Expected benefit payments in 2022 through 2026		327,000,000
Expected contributions in next fiscal year		$ 15,000,000
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Percentage of eligible compensation (up to)		75.00%
Contribution expenses		$ 99,000,000	$ 103,000,000	$ 83,000,000
U.S. Plans | First Part Of Pay Contribution
Defined Benefit Plan Disclosure [Line Items]
Company match employee contributions (as a percent)		100.00%
Employee contributions (as a percent)		3.00%
U.S. Plans | Second Part Of Pay Contribution
Defined Benefit Plan Disclosure [Line Items]
Company match employee contributions (as a percent)		50.00%
Employee contributions (as a percent)		2.00%
Pensjonsordningen for Apoteketaten (POA)
Defined Benefit Plan Disclosure [Line Items]
Percentage of total plan contribution (exceeding)		5.00%
Amounts of plan exceeding total plan contribution		$ 23,000,000	24,000,000	5,000,000
Funded status (as a percent)		66.00%
Amounts accrued for liability		$ 0
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Highest average pay period	60 months
Plan years prior to freeze date	15 years
Unexpected actuarial losses (as a percent) (exceeding)		10.00%
Prior service credit		$ 0	8,000,000	0
Actuarial loss		44,000,000	27,000,000	32,000,000
Projected benefit obligation		$ 535,000,000	$ 583,000,000	540,000,000
Discount rates		3.27%	3.18%
Increase in basis points		0.0009
U.S. Plans | Equity Investments
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocations (as a percent)		50.00%	50.00%
U.S. Plans | Fixed Income Investments
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocations (as a percent)		45.00%	45.00%
U.S. Plans | Real Estate
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocations (as a percent)		5.00%	5.00%
U.S. Plans | Unfunded plan
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation		$ 175,000,000	$ 189,000,000
Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Unit value of cash and cash equivalents (in dollars per share) | $ / shares		$ 1
Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Percentage of obligation		1.00%
Remediation period if shortfall exceeds threshold amount		2 years
Prior service credit		$ 2,000,000	2,000,000	2,000,000
Actuarial loss		5,000,000	5,000,000	4,000,000
Projected benefit obligation		$ 899,000,000	$ 963,000,000	$ 934,000,000
Discount rates		2.84%	2.50%
Increase in basis points		0.0034
Amount of plan asset value		$ 40,000,000	$ 39,000,000
Non-U.S. Plans | Unfunded plan
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation		$ 272,000,000	$ 222,000,000

Pension Benefits - Schedule Of

Pension Benefits - Schedule Of Net Periodic Expense For Pension Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost - benefits earned during the year	$ 4	$ 1	$ 4
Interest cost on projected benefit obligation	18	19	19
Expected return on assets	(19)	(21)	(20)
Amortization of unrecognized actuarial loss, prior service costs and net transitional obligation	42	19	32
Curtailment/settlement loss (gain)	2	0	0
Net periodic expense	47	18	35
Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost - benefits earned during the year	20	16	6
Interest cost on projected benefit obligation	24	34	11
Expected return on assets	(30)	(30)	(12)
Amortization of unrecognized actuarial loss, prior service costs and net transitional obligation	3	3	4
Curtailment/settlement loss (gain)	0	6	(1)
Net periodic expense	$ 17	$ 29	$ 8

Pension Benefits - Schedule 107

Pension Benefits - Schedule Of Changes In Benefit Obligations And Plan Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
U.S. Plans
Change in benefit obligations
Benefit obligation at beginning of period	$ 583	$ 540
Service cost	4	1	$ 4
Interest cost	18	19	19
Actuarial loss (gain)	(13)	53
Benefit payments	(54)	(30)
Amendments	0	0
Expenses paid	(3)	0
Foreign exchange impact and other	0	0
Benefit obligation at end of period	535	583	540
Change in plan assets
Fair value of plan assets at beginning of period	298	300
Actual return on plan assets	(3)	16
Employer and participant contributions	24	12
Benefits paid	(54)	(30)
Expenses paid	(3)	0
Foreign exchange impact and other	0	0
Fair value of plan assets at end of period	262	298	300
Funded status at end of period	(273)	(285)
Amounts recognized on the balance sheet
Assets	0	0
Current liabilities	(2)	(17)
Long-term liabilities	(271)	(268)
Total	(273)	(285)
Non-U.S. Plans
Change in benefit obligations
Benefit obligation at beginning of period	963	934
Service cost	20	16	6
Interest cost	24	34	11
Actuarial loss (gain)	(64)	194
Benefit payments	(35)	(49)
Amendments	(2)	(6)
Expenses paid	0	0
Foreign exchange impact and other	(7)	(160)
Benefit obligation at end of period	899	963	934
Change in plan assets
Fair value of plan assets at beginning of period	612	590
Actual return on plan assets	2	88
Employer and participant contributions	44	73
Benefits paid	(35)	(49)
Expenses paid	0	0
Foreign exchange impact and other	(16)	(90)
Fair value of plan assets at end of period	607	612	$ 590
Funded status at end of period	(292)	(351)
Amounts recognized on the balance sheet
Assets	21	0
Current liabilities	(11)	(6)
Long-term liabilities	(302)	(345)
Total	$ (292)	$ (351)

Pension Benefits - Schedule 108

Pension Benefits - Schedule Of Projected Benefit Obligation, Accumulated Benefit Obligation And Fair Value Of Plan Assets For Pension Plans (Details) - USD ($) $ in Millions	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ 535	$ 583	$ 540
Accumulated benefit obligation	535	583
Fair value of plan assets	262	298	300
Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	899	963	934
Accumulated benefit obligation	855	897
Fair value of plan assets	$ 607	$ 612	$ 590

Pension Benefits - Schedule 109

Pension Benefits - Schedule Of Amounts Recognized In Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	Mar. 31, 2016	Mar. 31, 2015
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss	$ 185	$ 220
Prior service credit	0	0
Total	185	220
Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss	133	175
Prior service credit	(11)	(6)
Total	$ 122	$ 169

Pension Benefits - Schedule 110

Pension Benefits - Schedule Of Other Changes In Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Amortization of:
Net actuarial loss	$ (47)
Prior service credit (cost)	1
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain)	9	$ 58	$ (31)
Prior service credit	0	0	(8)
Amortization of:
Net actuarial loss	(44)	(27)	(32)
Prior service credit (cost)	0	8	0
Foreign exchange impact and other	0	0	(1)
Total recognized in net periodic benefit cost and other comprehensive loss (income)	(35)	39	(72)
Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain)	(38)	117	12
Prior service credit	(5)	(8)	0
Amortization of:
Net actuarial loss	(5)	(5)	(4)
Prior service credit (cost)	2	2	2
Foreign exchange impact and other	(1)	(8)	4
Total recognized in net periodic benefit cost and other comprehensive loss (income)	$ (47)	$ 98	$ 14

Pension Benefits - Schedule 111

Pension Benefits - Schedule Of Weighted-Average Assumptions Used to Estimate Net Periodic Pension Expense and Actuarial Present Value of Benefit Obligations (Details)	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
U.S. Plans
Net periodic pension expense
Discount rates	3.36%	3.74%	3.39%
Rate of increase in compensation	4.00%	4.00%	4.00%
Expected long-term rate of return on plan assets	6.75%	7.25%	7.25%
Benefit obligation
Discount rates	3.27%	3.18%	3.58%
Rate of increase in compensation	4.00%	4.00%	4.00%
Non-U.S. Plans
Net periodic pension expense
Discount rates	2.36%	3.85%	3.95%
Rate of increase in compensation	2.80%	3.11%	2.66%
Expected long-term rate of return on plan assets	4.87%	5.39%	5.71%
Benefit obligation
Discount rates	2.84%	2.50%	3.92%
Rate of increase in compensation	2.98%	3.24%	3.27%

Pension Benefits - Schedule 112

Pension Benefits - Schedule Of Sensitivity To Changes In Weighted-Average Discount Rate For Pension Plans (Details) $ in Millions	12 Months Ended
	Mar. 31, 2016USD ($)
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation, one percentage point increase	$ (35)
Projected benefit obligation, one percentage point decrease	41
Net periodic pension cost, one percentage point increase	0
Net periodic pension cost, one percentage point decrease	0
Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation, one percentage point increase	(85)
Projected benefit obligation, one percentage point decrease	101
Net periodic pension cost, one percentage point increase	(4)
Net periodic pension cost, one percentage point decrease	$ 6

Pension Benefits - Summary Of P

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

Pension Benefits - Schedule 114

Pension Benefits - Schedule Of Reconciliation Of Level 3 Plan Assets Held (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
U.S. Plans
Change in plan assets
Fair value of plan assets at beginning of period	$ 298	$ 300
Fair value of plan assets at end of period	262	298
U.S. Plans | Level 3
Change in plan assets
Fair value of plan assets at beginning of period	18	16
Acquisitions	0	0
Unrealized gain on plan assets still held	1	2
Purchases, sales and settlements	(2)	0
Fair value of plan assets at end of period	17	18
U.S. Plans | Real Estate Funds
Change in plan assets
Fair value of plan assets at beginning of period	18
Fair value of plan assets at end of period	17	18
U.S. Plans | Real Estate Funds | Level 3
Change in plan assets
Fair value of plan assets at beginning of period	18	16
Acquisitions	0	0
Unrealized gain on plan assets still held	1	2
Purchases, sales and settlements	(2)	0
Fair value of plan assets at end of period	17	18
Non-U.S. Plans
Change in plan assets
Fair value of plan assets at beginning of period	612	590
Fair value of plan assets at end of period	607	612
Non-U.S. Plans | Level 3
Change in plan assets
Fair value of plan assets at beginning of period	30	12
Acquisitions	0	0
Unrealized gain on plan assets still held	(3)	1
Purchases, sales and settlements	0	17
Fair value of plan assets at end of period	27	30
Non-U.S. Plans | Real Estate Funds
Change in plan assets
Fair value of plan assets at beginning of period	26
Fair value of plan assets at end of period	24	26
Non-U.S. Plans | Real Estate Funds | Level 3
Change in plan assets
Fair value of plan assets at beginning of period	26	7
Acquisitions	0	0
Unrealized gain on plan assets still held	(2)	1
Purchases, sales and settlements	0	18
Fair value of plan assets at end of period	24	26
Non-U.S. Plans | Other | Level 3
Change in plan assets
Fair value of plan assets at beginning of period	4	5
Acquisitions	0	0
Unrealized gain on plan assets still held	(1)	0
Purchases, sales and settlements	0	(1)
Fair value of plan assets at end of period	$ 3	$ 4

Postretirement Benefits - Sched

Postretirement Benefits - Schedule Of Net Periodic Expense (Income) For Postretirement Welfare Benefits (Details) - Other Postretirement Benefit Plan, Defined Benefit - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1	$ 1	$ 2
Interest cost	4	5	5
Amortization of unrecognized actuarial gain and prior service credit	0	(4)	(1)
Curtailment/settlement loss (gain)	0	0	(2)
Net periodic expense	$ 5	$ 2	$ 4

Postretirement Benefits - Sc116

Postretirement Benefits - Schedule Of Changes In Benefit Obligations For Postretirement Welfare Plans (Details) - Other Postretirement Benefit Plan, Defined Benefit - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Change in benefit obligations
Benefit obligation at beginning of period	$ 118	$ 119
Service cost	1	1	$ 2
Interest cost	4	5	5
Plan amendments	(16)	0
Actuarial loss	3	5
Benefit payments	(11)	(12)
Curtailment gain	(1)	0
Benefit obligation at end of period	$ 98	$ 118	$ 119

Postretirement Benefits - Narra

Postretirement Benefits - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Expected amortization of actuarial loss from stockholders' equity in 2017	$ 15
Expected benefit payments in 2017	59
Expected benefit payments in 2018	174
Expected benefit payments in 2019	110
Expected benefit payments in 2020	66
Expected benefit payments in 2021	65
Other postretirement plan expected future benefit payments, 2022 through 2026	327
Expected contributions for postretirement benefit plans in 2016	15
Other Postretirement Benefit Plan, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss	4	$ 1
Net prior service credits for post retirement plans	16	1
Net actuarial loss for changes in benefit obligations	3	$ 9
Net prior service credits	16
Expected amortization of actuarial loss from stockholders' equity in 2017	1
Amortization of actuarial gain from stockholders' equity	1
Expected benefit payments in 2017	11
Expected benefit payments in 2018	9
Expected benefit payments in 2019	9
Expected benefit payments in 2020	8
Expected benefit payments in 2021	8
Other postretirement plan expected future benefit payments, 2022 through 2026	34
Expected contributions for postretirement benefit plans in 2016	$ 11
Weighted-average discount rates used to estimate postretirement welfare benefit expenses	3.59%	4.07%	3.84%
Weighted-average discount rates for actuarial present value of benefit obligations	3.68%	3.61%	4.08%
Amortization period	3 years
Assumed health care cost trend in measuring accumulated postretirement benefit obligation for prescription drugs (as a percent)	6.50%	6.75%
Other Postretirement Benefit Plan, Defined Benefit | Medical | Pre-65
Defined Benefit Plan Disclosure [Line Items]
Assumed health care cost trend in measuring accumulated postretirement benefit obligation for ages (as a percent)	7.00%	7.25%
Pension and other postretirement benefit plans, assumptions used calculating postretirement benefit obligation, age threshold	65 years
Other Postretirement Benefit Plan, Defined Benefit | Medical | Post-65
Defined Benefit Plan Disclosure [Line Items]
Assumed health care cost trend in measuring accumulated postretirement benefit obligation for ages (as a percent)	6.50%	6.75%
Pension and other postretirement benefit plans, assumptions used calculating postretirement benefit obligation, age threshold	65 years
Other Postretirement Benefit Plan, Defined Benefit | Dental
Defined Benefit Plan Disclosure [Line Items]
Assumed health care cost trend in measuring accumulated postretirement benefit obligation for ages (as a percent)	5.00%	5.00%

Hedging Activities - Narrative

Hedging Activities - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Forward Contracts | Derivatives Designated for Hedge Accounting
Derivative [Line Items]
Derivative, notional amount	$ 323	$ 399
Foreign Exchange Contract | Derivatives Designated for Hedge Accounting | Cross currency swaps (non-current)
Derivative [Line Items]
Derivative, notional amount	546
Foreign Exchange Contract | Derivatives Not Designated for Hedge Accounting
Derivative [Line Items]
Derivative, notional amount	876	1,755
Net gain (losses) on derivatives	$ 60	$ (189)

Hedging Activities - Schedule o

Hedging Activities - Schedule of Information Regarding Fair Value of Derivatives on a Gross Basis (Details) - USD ($) $ in Millions	Mar. 31, 2016	Mar. 31, 2015
Foreign Exchange Contract | Derivatives designated for hedge accounting
Derivatives, Fair Value [Line Items]
Fair value of derivative asset, gross fair value	$ 62	$ 67
Fair value of derivative liability, gross fair value	8	0
Foreign Exchange Contract | Derivatives designated for hedge accounting | Prepaid expenses and other
Derivatives, Fair Value [Line Items]
Fair value of derivative asset, gross fair value	16	14
Fair value of derivative liability, gross fair value	0	0
Derivative asset, notional amount	80	76
Foreign Exchange Contract | Derivatives designated for hedge accounting | Other Noncurrent Assets
Derivatives, Fair Value [Line Items]
Fair value of derivative asset, gross fair value	46	53
Fair value of derivative liability, gross fair value	0	0
Derivative asset, notional amount	243	323
Foreign Exchange Contract | Derivatives not designated for hedge accounting
Derivatives, Fair Value [Line Items]
Fair value of derivative asset, gross fair value	23	7
Fair value of derivative liability, gross fair value	0	79
Foreign Exchange Contract | Derivatives not designated for hedge accounting | Prepaid expenses and other
Derivatives, Fair Value [Line Items]
Fair value of derivative asset, gross fair value	23	7
Fair value of derivative liability, gross fair value	0	0
Derivative asset, notional amount	680	493
Foreign Exchange Contract | Derivatives not designated for hedge accounting | Other accrued liabilities
Derivatives, Fair Value [Line Items]
Fair value of derivative asset, gross fair value	0	0
Fair value of derivative liability, gross fair value	0	79
Derivative liability, notional amount	196	1,262
Currency Swap | Derivatives designated for hedge accounting | Other Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Fair value of derivative asset, gross fair value	0	0
Fair value of derivative liability, gross fair value	8	0
Derivative liability, notional amount	$ 546	$ 0

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Dec. 31, 2013	Mar. 31, 2014	Mar. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying amount of liabilities	$ 9,700			$ 8,100
Brazil Distribution Business
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Pre tax impairment charges	241
Impairment charges, after tax	235
International Technology
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Pre tax impairment charges		$ 80
Impairment charges, after tax		$ 80
Level 2 | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value of liabilities	10,400			$ 8,600
Level 3 | Fair Value, Measurements, Nonrecurring | Brazil Distribution Business
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Pre tax impairment charges	241
Impairment charges, after tax	$ 235
Level 3 | Fair Value, Measurements, Nonrecurring | International Technology
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Pre tax impairment charges			$ 80

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Fair Value Measurements, Recurring (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Millions	Mar. 31, 2016	Mar. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	$ 2,413	$ 4,217
Money Market Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	2,413	2,880
Time Deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	0	94
Repurchase Agreements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	0	1,243
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	2,413	4,123
Level 1 | Money Market Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	2,413	2,880
Level 1 | Time Deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	0	0
Level 1 | Repurchase Agreements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	0	1,243
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	0	94
Level 2 | Money Market Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	0	0
Level 2 | Time Deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	0	94
Level 2 | Repurchase Agreements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	0	0
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	0	0
Level 3 | Money Market Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	0	0
Level 3 | Time Deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	0	0
Level 3 | Repurchase Agreements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents	$ 0	$ 0

Lease Obligations - Schedule Of

Lease Obligations - Schedule Of Future Minimum Rental Payments For Operating Leases (Details) $ in Millions	Mar. 31, 2016USD ($)
Noncancelable Operating Leases
2,017	$ 363
2,018	309
2,019	252
2,020	209
2,021	168
Thereafter	669
Total minimum lease payments	$ 1,970

Lease Obligations - Narrative (

Lease Obligations - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Operating Leased Assets [Line Items]
Minimum sublease rentals, due under future noncancelable subleases	$ 45
Rent expense	$ 433	$ 440	$ 298
Renewal option increments for leases	5 years
Building | Minimum
Operating Leased Assets [Line Items]
Lease term	1 year
Building | Maximum
Operating Leased Assets [Line Items]
Lease term	14 years
Equipment | Minimum
Operating Leased Assets [Line Items]
Lease term	1 year
Equipment | Maximum
Operating Leased Assets [Line Items]
Lease term	8 years

Financial Guarantees and War124

Financial Guarantees and Warranties (Details)	12 Months Ended
	Mar. 31, 2016USD ($)
Guarantor Obligations [Line Items]
Guarantor obligations, current carrying value	$ 1,000,000
Guarantee obligations, expiring in 2017	194,000,000
Guarantee obligations, expiring in 2018	8,000,000
Guarantee obligations, expiring in 2019	10,000,000
Guarantee obligations, expiring in 2020	12,000,000
Guarantee obligations, expiring in 2021	12,000,000
Guarantee obligations, expiring after 2021	104,000,000
Guarantee Obligations Inventory Repurchase Guarantees
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure	$ 201,000,000
Guarantee Obligations Inventory Repurchase Guarantees | Minimum
Guarantor Obligations [Line Items]
Debt guarantee period	1 year
Guarantee Obligations Inventory Repurchase Guarantees | Maximum
Guarantor Obligations [Line Items]
Debt guarantee period	2 years
Guarantee Obligations Customers Debt
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure	$ 139,000,000
Guarantee Obligations Customers Debt | Minimum
Guarantor Obligations [Line Items]
Debt guarantee period	1 year
Guarantee Obligations Customers Debt | Maximum
Guarantor Obligations [Line Items]
Debt guarantee period	12 years
Standby Letters of Credit
Guarantor Obligations [Line Items]
Letters of credit outstanding	$ 142,000,000
Commitment to Investee Building and Equipment Construction
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure	$ 4,000,000

Commitments and Contingent L125

Commitments and Contingent Liabilities (Details) $ in Millions	Jan. 26, 2016relator	Apr. 16, 2013staterelatordefendant	Mar. 31, 2015USD ($)	Mar. 31, 2016USD ($)site	Mar. 31, 2015USD ($)	Mar. 31, 2014USD ($)
Loss Contingencies [Line Items]
Claim and litigation charges				$ 0	$ 150	$ 68
Payments for legal settlements				$ 0	0	105
Anti-Kickback Claim
Loss Contingencies [Line Items]
Number of relators | relator		2
Number of states filed on behalf of | state		21
Number of additional defendants | defendant		5
Controlled Substance Investigation
Loss Contingencies [Line Items]
Number of relators | relator	3
Claim and litigation charges			$ 150
Claims and litigation charges, after tax			$ 150		$ 150
Controlled Substance Investigation | Aurora, Colorado | All Controlled Substances
Loss Contingencies [Line Items]
Suspension period			3 years
Controlled Substance Investigation | Livonia, Michigan | All Controlled Substances
Loss Contingencies [Line Items]
Suspension period			2 years
Controlled Substance Investigation | Washington Courthouse, Ohio | All Controlled Substances
Loss Contingencies [Line Items]
Suspension period			2 years
Controlled Substance Investigation | Lakeland, Florida | Hydromorphone
Loss Contingencies [Line Items]
Suspension period			1 year
Environmental Litigation
Loss Contingencies [Line Items]
Number of sites | site				5
Remediation costs				$ 8.1
Hazardous substance sites, number | site				15
Estimated environmental assessment and cleanup costs				$ 1,380
Estimated loss				$ 26
Environmental Litigation | Minimum
Loss Contingencies [Line Items]
Time frame of disbursements				Apr. 1, 2016
Environmental Litigation | Maximum
Loss Contingencies [Line Items]
Time frame of disbursements				Mar. 31, 2046
Average Wholesale Price Litigation
Loss Contingencies [Line Items]
Claim and litigation charges						68
Payments for legal settlements						$ 105

Stockholders' Equity - Narrativ

Stockholders' Equity - Narrative (Details) $ / shares in Units, shares in Millions, $ in Millions	1 Months Ended		3 Months Ended	12 Months Ended
	Feb. 29, 2016USD ($)	Jul. 31, 2015$ / shares	Mar. 31, 2016USD ($)vote$ / sharesshares	Mar. 31, 2016USD ($)vote$ / sharesshares	Mar. 31, 2015USD ($)$ / sharesshares	Mar. 31, 2014USD ($)$ / sharesshares	Mar. 31, 2013USD ($)
Dividends Payable [Line Items]
Number of votes | vote			1	1
Cash dividends declared per common share (in dollars per share) | $ / shares				$ 1.08	$ 0.96	$ 0.92
Shares bought | shares				8.7	1.5	0
Shares repurchased				$ 1,504	$ 340	$ 0
Average price paid per share (in dollars per share) | $ / shares				$ 173.64	$ 226.55	$ 0
Total authorization outstanding for repurchases of common stock			$ 996	$ 996	$ 0	$ 340	$ 340
Treasury stock retired (in shares) | shares				115.5
Retirement of common stock				$ 0
Net foreign currency translation gains (losses)				$ 172	(1,989)	83
Treasury Stock
Dividends Payable [Line Items]
Treasury stock retired (in shares) | shares				116
Retirement of common stock				$ 7,848
Retained Earnings
Dividends Payable [Line Items]
Retirement of common stock				6,354
Additional Paid-in Capital
Dividends Payable [Line Items]
Retirement of common stock				1,493
Accumulated Foreign Currency Adjustment Including Portion Attributable to Noncontrolling Interest
Dividends Payable [Line Items]
Net foreign currency translation gains (losses)				113	(1,855)	53
Other comprehensive income (loss) before reclassifications				113	(1,845)	$ 9
Accumulated Foreign Currency Adjustment Attributable to Noncontrolling Interest
Dividends Payable [Line Items]
Net foreign currency translation gains (losses)				16	(267)
Accumulated Defined Benefit Plans Adjustment, Net Prior Service Including Portion Attributable to Noncontrolling Interest
Dividends Payable [Line Items]
Other comprehensive income (loss) before reclassifications				$ 4	$ (12)
Open Market Transactions
Dividends Payable [Line Items]
Shares bought | shares				4.5
Shares repurchased				$ 854
Average price paid per share (in dollars per share) | $ / shares				$ 192.27
Accelerated Share Repurchase
Dividends Payable [Line Items]
Shares bought | shares			4.2
Shares repurchased	$ 650
Average price paid per share (in dollars per share) | $ / shares			$ 154.04
Minimum
Dividends Payable [Line Items]
Cash dividends declared per common share (in dollars per share) | $ / shares		$ 0.24
Maximum
Dividends Payable [Line Items]
Cash dividends declared per common share (in dollars per share) | $ / shares		$ 0.28

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Share Repurchases (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014	Oct. 31, 2015	May. 31, 2015
Stockholders' Equity Note [Abstract]
Total Number of Shares Purchased	8.7	1.5	0
Average price paid per share (in dollars per share)	$ 173.64	$ 226.55	$ 0
Approximate Dollar Value of Shares that May Yet Be Purchased Under the Programs
Beginning balance	$ 0	$ 340	$ 340
Shares repurchased	(1,504)	(340)	0
Shares repurchase plans authorized				$ 2,000	$ 500
Ending balance	$ 996	$ 0	$ 340

Stockholders' Equity - Sched128

Stockholders' Equity - Schedule of Other Comprehensive Income (Loss), Net of Tax (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Net of Tax	$ 172	$ (1,989)	$ 83
Foreign Currency Translation Adjustments, Net of Tax
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	113	(1,845)	9
Amounts reclassified to earnings	0	(10)	44
Other Comprehensive Income (Loss), Net of Tax	113	(1,855)	53
Tax expense (benefit)	(23)	0	0
Reclassification, tax expense	0	0	24
Unrealized Losses on Cash Flow Hedges, Net of Tax
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	6	(13)	(6)
Amounts reclassified to earnings	3	3	0
Other Comprehensive Income (Loss), Net of Tax	9	(10)	(6)
Tax expense (benefit)	0	0	0
Reclassification, tax expense	0	0	0
Changes in Retirement-Related Benefit Plans, Net Actuarial Gain (Loss) and Prior Service Credit (Cost)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	23	(140)	17
Amounts reclassified to earnings	30	11	22
Tax expense (benefit)	13	(66)	16
Reclassification, tax expense	18	6	12
Changes in Retirement-Related Benefit Plans, Foreign Currency Translation Adjustments and Other
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	(3)	4	(4)
Amounts reclassified to earnings	0	1	1
Tax expense (benefit)	0	0	0
Reclassification, tax expense	$ 0	$ 0	$ 1

Stockholders' Equity - Sched129

Stockholders' Equity - Schedule of Changes in Accumulated Other Comprehensive Income by Component (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Accumulated Other Comprehensive Income (Loss), Change, Net of Tax [Roll Forward]
Beginning balance	$ 8,085	$ 10,318	$ 7,070
Other Comprehensive Income (Loss), Net of Tax	172	(1,989)	83
Other comprehensive income (loss) attributable to McKesson	152	(1,884)	83
Ending balance	9,008	8,085	10,318
Foreign Currency Translation Adjustments, Net of Tax
Accumulated Other Comprehensive Income (Loss), Change, Net of Tax [Roll Forward]
Beginning balance	(1,420)	168
Other comprehensive income (loss) before reclassifications	113	(1,845)	9
Amounts reclassified to earnings	0	(10)	44
Other Comprehensive Income (Loss), Net of Tax	113	(1,855)	53
Less: amounts attributable to noncontrolling and redeemable interests	16	(267)
Other comprehensive income (loss) attributable to McKesson	97	(1,588)
Ending balance	(1,323)	(1,420)	168
Unrealized Losses on Cash Flow Hedges, Net of Tax
Accumulated Other Comprehensive Income (Loss), Change, Net of Tax [Roll Forward]
Beginning balance	(21)	(11)
Other comprehensive income (loss) before reclassifications	6	(13)	(6)
Amounts reclassified to earnings	3	3	0
Other Comprehensive Income (Loss), Net of Tax	9	(10)	(6)
Less: amounts attributable to noncontrolling and redeemable interests	0	0
Other comprehensive income (loss) attributable to McKesson	9	(10)
Ending balance	(12)	(21)	(11)
Unrealized Net Gains (Losses) and Other Components of Benefit Plans, Net of Tax
Accumulated Other Comprehensive Income (Loss), Change, Net of Tax [Roll Forward]
Beginning balance	(272)	(160)
Other comprehensive income (loss) before reclassifications	23	(136)
Amounts reclassified to earnings	27	12
Other Comprehensive Income (Loss), Net of Tax	50	(124)	36
Less: amounts attributable to noncontrolling and redeemable interests	4	(12)
Other comprehensive income (loss) attributable to McKesson	46	(112)
Ending balance	(226)	(272)	(160)
Total Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss), Change, Net of Tax [Roll Forward]
Beginning balance	(1,713)	(3)	(65)
Other comprehensive income (loss) before reclassifications	142	(1,994)
Amounts reclassified to earnings	30	5
Other Comprehensive Income (Loss), Net of Tax	172	(1,989)
Less: amounts attributable to noncontrolling and redeemable interests	20	(279)
Other comprehensive income (loss) attributable to McKesson	152	(1,710)	62
Ending balance	$ (1,561)	$ (1,713)	$ (3)

Related Party Balances and T130

Related Party Balances and Transactions (Details) - Investee - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Related Party Transaction [Line Items]
Revenue from related parties	$ 112	$ 114
Accounts receivable, related parties, current	$ 8	$ 9

Segments of Business - Narrativ

Segments of Business - Narrative (Details) $ in Millions	3 Months Ended				12 Months Ended
	Mar. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Mar. 31, 2016USD ($)segment	Mar. 31, 2015USD ($)	Mar. 31, 2014USD ($)
Segment Reporting [Abstract]
Number of operating segments | segment					2
Segment Reporting Information [Line Items]
Pretax charges					$ 3,545	$ 2,968	$ 2,439
Pre-tax gain					103	0	0
Pre-tax charge	$ 229				229
Operating Segments
Segment Reporting Information [Line Items]
Pretax charges					4,072	$ 3,485	$ 2,920
Corporate
Segment Reporting Information [Line Items]
Pre-tax charge	17				$ 17
Distribution Solutions | Operating Segments
Segment Reporting Information [Line Items]
Percentage of total revenue (less than) (as a percent)					2.00%	2.00%	2.00%
Pretax charges					$ 3,553	$ 3,047	$ 2,472
Net cash proceeds		$ 17		$ 59	76
Pre-tax charge	161				161
Distribution Solutions | Operating Segments | ZEE Medical Business
Segment Reporting Information [Line Items]
Pre-tax gain			$ 52		52
Distribution Solutions | Operating Segments | LIFO method of accounting
Segment Reporting Information [Line Items]
Pretax charges					244	337	311
Technology Solutions | Operating Segments
Segment Reporting Information [Line Items]
Pretax charges					519	438	$ 448
Pre-tax charge	$ 51				51
Technology Solutions | Operating Segments | Nurse Triage
Segment Reporting Information [Line Items]
Pre-tax gain				$ 51	$ 51
Technology Solutions | Operating Segments | International Technology, Workforce
Segment Reporting Information [Line Items]
Non-cash pre-tax charge						$ 34

Segments of Business - Schedule

Segments of Business - Schedule Of Segment Information (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Revenues
Total Revenues	$ 46,678	$ 47,899	$ 48,761	$ 47,546	$ 44,925	$ 46,484	$ 44,160	$ 43,476	$ 190,884	$ 179,045	$ 137,392
Operating profit
Total									3,545	2,968	2,439
Interest Expense									(353)	(374)	(300)
Income From Continuing Operations Before Income Taxes									3,250	2,657	2,171
Depreciation and amortization
Total									885	1,017	735
Expenditures for long-lived assets
Total									488	376	278
United States
Revenues
Total Revenues									158,255	142,810	122,426
Foreign
Revenues
Total Revenues									32,629	36,235	14,966
Operating Segments
Revenues
Total Revenues									190,884	179,045	137,392
Operating profit
Total									4,072	3,485	2,920
Operating Segments | Distribution Solutions
Revenues
Total Revenues									187,999	175,976	134,062
Operating profit
Total									3,553	3,047	2,472
Depreciation and amortization
Total									669	750	446
Expenditures for long-lived assets
Total									306	301	179
Operating Segments | Distribution Solutions | Reportable Subsegments | North America pharmaceutical distribution and services
Revenues
Total Revenues									158,469	143,711	123,929
Operating Segments | Distribution Solutions | Reportable Subsegments | International pharmaceutical distribution and services
Revenues
Total Revenues									23,497	26,358	4,485
Operating Segments | Distribution Solutions | Reportable Subsegments | Medical-Surgical distribution and services
Revenues
Total Revenues									6,033	5,907	5,648
Operating Segments | Technology Solutions
Revenues
Total Revenues									2,885	3,069	3,330
Operating profit
Total									519	438	448
Depreciation and amortization
Total									107	156	169
Expenditures for long-lived assets
Total									15	27	47
Corporate Expenses, Net
Operating profit
Corporate Expenses, Net									(469)	(454)	(449)
Depreciation and amortization
Total									109	111	120
Expenditures for long-lived assets
Total									167	48	52
Segment Reconciling Items
Operating profit
Interest Expense									$ (353)	$ (374)	$ (300)

Segments of Business - Segment

Segments of Business - Segment Assets and Property, Plant and Equipment, Net by Geographical Area (Details) - USD ($) $ in Millions	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Segment assets
Cash and cash equivalents	$ 4,048	$ 5,341	$ 4,193	$ 2,456
Total	56,563	53,870
Property, plant and equipment, net
Total	2,278	2,045
United States
Property, plant and equipment, net
Total	1,500	1,273
Foreign
Property, plant and equipment, net
Total	778	772
Operating Segments
Segment assets
Total	50,160	47,263
Corporate
Segment assets
Cash and cash equivalents	4,048	5,341
Other	2,355	1,266
Distribution Solutions | Operating Segments
Segment assets
Total	47,088	43,982
Technology Solutions | Operating Segments
Segment assets
Total	$ 3,072	$ 3,281

Quarterly Financial Informat134

Quarterly Financial Information (Unaudited) - Narrative (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Quarterly Financial Information [Line Items]
Pretax charges related to last-in-first-out method of accounting for inventories									$ 244	$ 337	$ 311
Pre-tax charge	$ 229								229
Brazil Distribution Business
Quarterly Financial Information [Line Items]
Impairment charges, net of tax					$ 235
Controlled Substance Investigation
Quarterly Financial Information [Line Items]
Claims and litigation charges, after tax					150					$ 150
Cost of Sales
Quarterly Financial Information [Line Items]
Pre-tax charge	26
Operating Expenses
Quarterly Financial Information [Line Items]
Pre-tax charge	203
Operating Segments | Distribution Solutions
Quarterly Financial Information [Line Items]
Pretax charges related to last-in-first-out method of accounting for inventories	29	$ 33	$ 91	$ 91	$ 50	$ 95	$ 94	$ 98
Net cash proceeds		$ 17		59					76
Pre-tax charge	161								161
Operating Segments | Distribution Solutions | ZEE Medical Business
Quarterly Financial Information [Line Items]
Gain from sale of business, after tax			$ 29
Operating Segments | Distribution Solutions | Cost of Sales
Quarterly Financial Information [Line Items]
Pre-tax charge	5
Operating Segments | Distribution Solutions | Operating Expenses
Quarterly Financial Information [Line Items]
Pre-tax charge	156
Operating Segments | Technology Solutions
Quarterly Financial Information [Line Items]
Pre-tax charge	51								$ 51
Operating Segments | Technology Solutions | Nurse Triage
Quarterly Financial Information [Line Items]
Gain from sale of business, after tax				$ 38
Operating Segments | Technology Solutions | Cost of Sales
Quarterly Financial Information [Line Items]
Pre-tax charge	21
Operating Segments | Technology Solutions | Operating Expenses
Quarterly Financial Information [Line Items]
Pre-tax charge	$ 30

Quarterly Financial Informat135

Quarterly Financial Information (Unaudited) - Schedule Of Quarterly Financial Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Revenues	$ 46,678	$ 47,899	$ 48,761	$ 47,546	$ 44,925	$ 46,484	$ 44,160	$ 43,476	$ 190,884	$ 179,045	$ 137,392
Gross profit	2,852	2,872	2,844	2,848	2,917	2,898	2,864	2,732	11,416	11,411	8,352
Income after income taxes:
Continuing operations	465	642	636	599	411	521	491	419	2,342	1,842	1,414
Discontinued operations	(21)	5	(6)	(10)	(267)	(10)	(14)	(8)	(32)	(299)	(156)
Net Income	444	647	630	589	144	511	477	411	2,310	1,543	1,258
Net income attributable to McKesson	$ 431	$ 634	$ 617	$ 576	$ 132	$ 472	$ 469	$ 403	$ 2,258	$ 1,476	$ 1,263
Diluted
Continuing operations (in dollars per share)	$ 1.97	$ 2.71	$ 2.65	$ 2.50	$ 1.69	$ 2.04	$ 2.05	$ 1.76	$ 9.84	$ 7.54	$ 6.08
Discontinued operations (in dollars per share)	(0.09)	0.02	(0.02)	(0.05)	(1.13)	(0.04)	(0.06)	(0.04)	(0.14)	(1.27)	(0.67)
Total (in dollars per share)	1.88	2.73	2.63	2.45	0.56	2	1.99	1.72	9.70	6.27	5.41
Basic
Continuing operations (in dollars per share)	1.99	2.74	2.68	2.53	1.72	2.07	2.08	1.79	9.96	7.66	6.19
Discontinued operations (in dollars per share)	(0.09)	0.02	(0.02)	(0.04)	(1.15)	(0.04)	(0.06)	(0.04)	(0.14)	(1.29)	(0.68)
Total (in dollars per share)	$ 1.90	$ 2.76	$ 2.66	$ 2.49	$ 0.57	$ 2.03	$ 2.02	$ 1.75	$ 9.82	$ 6.37	$ 5.51

SUPPLEMENTARY CONSOLIDATED F136

SUPPLEMENTARY CONSOLIDATED FINANCIAL STATEMENT SCHEDULE VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	$ 174	$ 134	$ 136
Charged to Costs and Expense	113	75	36
Charged to Other Accounts	(1)	0	(1)
Deductions From Allowance Accounts	(33)	(35)	(37)
Balance at End of Year	253	174	134
Allowances for doubtful accounts
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	141	112	121
Charged to Costs and Expense	113	67	36
Charged to Other Accounts	2	0	(11)
Deductions From Allowance Accounts	(44)	(38)	(34)
Balance at End of Year	212	141	112
Other allowances
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	33	22	15
Charged to Costs and Expense	0	8	0
Charged to Other Accounts	(3)	0	10
Deductions From Allowance Accounts	11	3	(3)
Balance at End of Year	41	33	22
Written off
Valuation and Qualifying Accounts Disclosure [Line Items]
Deductions From Allowance Accounts	(33)	(34)	(39)
Credited to other accounts
Valuation and Qualifying Accounts Disclosure [Line Items]
Deductions From Allowance Accounts	0	(1)	2
Amounts shown as deductions from current and non-current receivables
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	174	134
Balance at End of Year	$ 253	$ 174	$ 134