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Number of Largest Customers

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Revenue from Contract with Customer, Excluding Assessed Tax, Sales Returns

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- Definition

For each balance sheet presented, the amount of accumulated amortization for capitalized computer software costs.

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The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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- Definition

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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No definition available.

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Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to excess tax benefit for share-based compensation cost.

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods.

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The change in the inventory reserve representing the cumulative difference in cost between the first in, first out and the last in, first out inventory valuation methods, which change has been reflected in the statement of income during the period.

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- Definition

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

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No definition available.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

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The percentage of LIFO (last in first out) inventory to total inventory as of the balance sheet date if other than 100 percent.

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No definition available.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Significant Accounting Policies (Details) $ in Millions	3 Months Ended								12 Months Ended
Significant Accounting Policies (Details) $ in Millions	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2019 USD ($) customer segment	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)	Apr. 01, 2019 USD ($)	Apr. 01, 2018 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of operating segments \| segment									3
LIFO inventory (percentage)	62.00%				63.00%				62.00%	63.00%
LIFO reserve	$ 696				$ 906				$ 696	$ 906
Credits associated with last-in, first-out inventory method	146	$ 21	$ 22	$ 21	94	$ 2	$ 29	$ (26)	210	99	$ 7
Capitalized software held for internal use, net	394				425				394	425
Capitalized software held for internal use, accumulated amortization	$ 1,246				$ 1,182				1,246	1,182
Sales returns from customers									2,900		3,100
Opening Retained Earnings Adjustments: Adoption of New Accounting Standards													$ 154
Tax expense (benefit) related to adoption of amended accounting guidance									$ 4	(8)	(54)
Minimum
New Accounting Pronouncements or Change in Accounting Principle [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
New Accounting Pronouncements or Change in Accounting Principle [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
Customer Concentration Risk \| Sales Revenue, Net
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of largest customers \| customer									10
Percentage of total consolidated revenues (percent)									49.90%
Customer Concentration Risk \| Sales Revenue, Net \| CVS
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Percentage of total consolidated revenues (percent)									19.40%
Customer Concentration Risk \| Accounts Receivable
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of largest customers \| customer									10
Percentage of total consolidated revenues (percent)									31.90%
Customer Concentration Risk \| Accounts Receivable \| CVS
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Percentage of total consolidated revenues (percent)									18.40%
Accounting Standards Update 2016-16
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Opening Retained Earnings Adjustments: Adoption of New Accounting Standards													$ 152
New Accounting Pronouncement, Early Adoption, Effect
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Tax expense (benefit) related to adoption of amended accounting guidance									$ 4
Shipping and Handling \| Selling, Distribution and Administrative Expenses
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Shipping and handling costs									$ 951	$ 914	$ 814
Distribution and Retail Business \| Product Concentration Risk \| Sales Revenue, Net
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Percentage of total consolidated revenues (percent)									98.00%
Services Business \| Product Concentration Risk \| Sales Revenue, Net
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Percentage of total consolidated revenues (percent)									2.00%
Subsequent Event \| Expected \| Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease liability												$ 2,000