Accounts Receivable, Net - Summary of Accounts Receivable, Net (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Receivables [Abstract]
Noninsurance customer receivables	$ 5,534	$ 5,143
Pharmaceutical manufacturers receivable	4,676	3,439
Insurance customer receivables	1,789	2,321
Other receivables	192	334
Total		11,237
Accounts receivable, net classified as assets of business held for sale		(521)
Accounts receivable, net per Consolidated Balance Sheets	$ 12,191	$ 10,716

Receivables due from customers under insurance contracts.

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- Definition

Receivables due from customers that are not under insurance contracts. These include pharmacy sales and fees due from employer clients.

+ References

No definition available.

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- Definition

Receivables due from pharmaceutical manufacturers related to rebate contracts.

+ References

No definition available.

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- Definition

Receivables, Net, Current, Including Disposal Groups

+ References

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- Definition

Amount, after allowance, receivable from customers, clients, or other third-parties, and receivables classified as other due within one year or the normal operating cycle, if longer.

+ References

No definition available.

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- Definition

Amount classified as accounts, notes and loans receivable attributable to disposal group held for sale or disposed of.

+ References

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- Definition

The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

+ References

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