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Number Of Accounting Standards Adopted

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Accruals for Medicaid rebates, Medicare rebates, performance-based contract rebates, sales allowances and chargebacks, which are substantially all are included in Other current liabilities in our consolidated balance sheets.

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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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Amount of the cumulative effect on retained earnings before related income tax effect.

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Amount of the cumulative effect on retained earnings net of related income tax effect.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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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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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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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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Amount of lessee's right to use underlying asset under operating lease.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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Basis of Presentation and Significant Accounting Policies (Details) $ / shares in Units, $ in Millions				3 Months Ended	6 Months Ended	12 Months Ended
	Jul. 30, 2019 USD ($) $ / shares	Jul. 01, 2019 USD ($)	Jan. 01, 2019 USD ($) Accounting_standard	Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($) Operating_Segment	Dec. 31, 2018 USD ($) Operating_Segment	Jun. 28, 2020	Jan. 01, 2018 Accounting_standard
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of business segments \| Operating_Segment					3	2
Number of accounting standards adopted \| Accounting_standard			4					11
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
ROU assets				$ 1,273	$ 1,273
Lease liabilities (long-term)				1,026	1,026
Accrued rebates and other accruals				5,574	5,574	$ 5,426
Variable lease payments				$ 59	$ 118
Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
ROU assets			$ 1,400
Lease liabilities (long-term)			1,400
Cumulative effect adjustment to retained earnings, pre-tax			30
Cumulative effect adjustment to retained earnings, after-tax			$ 20
Minimum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease term				1 year	1 year
Operating lease term, option to extend					5 years
Maximum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease term				30 years	30 years
Operating lease term, option to extend					10 years
Therachon [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Percentage of voting interests previously acquired						3.00%
Subsequent Event [Member] \| Array [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Business acquisition, per share in cash (in dollars per share) \| $ / shares	$ 48
Payments for acquisitions, cash portion	$ 11,400
Subsequent Event [Member] \| Therachon [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Payments for acquisitions, cash portion		$ 340
Maximum amount of potential milestone payments		$ 470
Upjohn And Mylan [Member] \| Forecast [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Ownership percentage							57.00%
Upjohn And Mylan [Member] \| Mylan [Member] \| Forecast [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Ownership percentage by noncontrolling owners							43.00%