Condensed Consolidated Statements of Cash Flows (USD $) In Millions	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Cash flows from operating activities:
Cash receipts from customers	$ 72,875	$ 68,524
Cash paid for inventory and prescriptions dispensed by retail network pharmacies	(55,625)	(52,953)
Cash paid to other suppliers and employees	(10,092)	(10,346)
Interest received	3	3
Interest paid	(454)	(439)
Income taxes paid	(1,672)	(1,785)
Net cash provided by operating activities	5,035	3,004
Cash flows from investing activities:
Purchases of property and equipment	(1,168)	(1,379)
Proceeds from sale-leaseback transactions	11	124
Proceeds from sale of property and equipment	1	24
Acquisitions (net of cash acquired) and other investments	(1,406)	(158)
Purchase of short-term investments	(3)
Maturity of short-term investments	2	1
Net cash used in investing activities	(2,563)	(1,388)
Cash flows from financing activities:
Increase in short-term debt	230	1,069
Proceeds from issuance of long-term debt	1,463	991
Repayments of long-term debt	(1,149)	(2,102)
Dividends paid	(508)	(360)
Derivative settlements	(19)	(5)
Proceeds from exercise of stock options	341	171
Excess tax benefits from stock-based compensation	12	13
Repurchase of common stock	(2,553)	(1,500)
Other	(9)
Net cash used in financing activities	(2,192)	(1,723)
Net increase (decrease) in cash and cash equivalents	280	(107)
Cash and cash equivalents at beginning of period	1,427	1,086
Cash and cash equivalents at end of period	1,707	979
Reconciliation of net income to net cash provided by operating activities:
Net income	2,394	2,399
Adjustments required to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	1,172	1,096
Stock-based compensation	100	112
Deferred income taxes and other non-cash items	134	43
Change in operating assets and liabilities, net of effects of acquisitions:
Accounts receivable, net	(479)	346
Inventories	316	(242)
Other current assets	(173)	(41)
Other assets	(52)	11
Accounts payable and claims and discounts payable	716	(112)
Accrued expenses	980	(567)
Other long-term liabilities	(73)	(41)
Net cash provided by operating activities	$ 5,035	$ 3,004

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).