Amount of long-term debt assumed at the acquisition date.

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Amount of assets acquired at the acquisition date.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of other assets expected to be realized or consumed before one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of other liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of deferred tax liability attributable to taxable temporary differences assumed at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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The amount of inventory recognized as of the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Mergers, Acquisitions and Dispositions - Purchase Price Allocation (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 20, 2018	Dec. 31, 2017
Purchase price allocation [Abstract]
Goodwill	$ 44,602	$ 44,505		$ 6,164
Health Services [Member]
Purchase price allocation [Abstract]
Goodwill	$ 33,700
Express Scripts Holding Company [Member]
Purchase price allocation [Abstract]
Cash and cash equivalents			$ 3,517
Receivables			7,832
Inventory			2,472
Other current assets			600
Property and equipment			2,924
Goodwill			38,364
Other identifiable intangible assets			38,725
Other assets acquired, non-current			314
Total assets acquired			94,748
Other current liabilities			18,479
Long-term debt, including current portion			12,816
Deferred income tax liabilities			9,558
Other liabilities, non-current assumed			1,085
Total liabilities acquired			41,938
Total			52,810
Express Scripts Holding Company [Member] \| Health Services [Member]
Purchase price allocation [Abstract]
Goodwill			$ 33,700