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 difference assumed at the acquisition date that are classified as noncurrent.

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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 and Acquisitions - Purchase Price Allocation (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 20, 2018	Dec. 31, 2017	Dec. 31, 2016
Purchase price allocation [Abstract]
Goodwill	$ 44,505		$ 6,164	$ 5,980
Health Services [Member]
Purchase price allocation [Abstract]
Goodwill	$ 33,700	$ 33,700
Express Scripts Holding Company [Member] \| Health Services [Member]
Purchase price allocation [Abstract]
Cash and cash equivalents		3,517
Receivables		7,802
Inventory		2,483
Other current assets		600
Property and equipment		2,973
Goodwill		38,361
Other identifiable intangible assets		38,725
Other assets acquired, non-current		314
Total assets acquired		94,775
Other current liabilities		18,616
Long-term debt, including current portion		12,816
Deferred income tax liabilities		9,511
Other liabilities, non-current assumed		1,022
Total liabilities acquired		41,965
Total		$ 52,810