CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	$ 8,084	$ 5,269	$ 2,288	$ 2,641
OPERATING ACTIVITIES:
Net income (loss)	82	130	(87)	561
Adjustments to reconcile net income (loss) to net cash from operating activities:
Depreciation of property and equipment, including internal-use software and website development, and other amortization	700	457	2,402	1,338
Stock-based compensation	229	160	901	605
Other operating expense (income), net	31	46	139	168
Losses (gains) on sales of marketable securities, net		(2)	(7)	(8)
Other expense (income), net	68	15	306	(78)
Deferred income taxes	(80)	(38)	(307)	83
Excess tax benefits from stock-based compensation		(40)	(390)	(56)
Changes in operating assets and liabilities:
Inventories	535	747	(1,211)	(1,374)
Accounts receivable, net and other	729	746	(877)	(479)
Accounts payable	(4,187)	(4,258)	2,141	1,388
Accrued expenses and other	(703)	(529)	864	721
Additions to unearned revenue	684	397	2,083	1,252
Amortization of previously unearned revenue	(460)	(269)	(1,712)	(1,070)
Net cash provided by (used in) operating activities	(2,372)	(2,438)	4,245	3,051
INVESTING ACTIVITIES:
Purchases of property and equipment, including internal-use software and website development	(670)	(386)	(4,068)	(1,899)
Acquisitions, net of cash acquired, and other	(103)	(50)	(798)	(615)
Sales and maturities of marketable securities and other investments	599	1,738	3,098	6,641
Purchases of marketable securities and other investments	(776)	(852)	(3,227)	(5,997)
Net cash provided by (used in) investing activities	(950)	450	(4,995)	(1,870)
FINANCING ACTIVITIES:
Excess tax benefits from stock-based compensation		40	390	56
Common stock repurchased		(960)		(1,237)
Proceeds from long-term debt and other	25	68	3,319	154
Repayments of long-term debt, capital lease, and finance lease obligations	(182)	(153)	(603)	(483)
Net cash provided by (used in) financing activities	(157)	(1,005)	3,106	(1,510)
Foreign-currency effect on cash and cash equivalents	(124)	12	(163)	(24)
Net increase (decrease) in cash and cash equivalents	(3,603)	(2,981)	2,193	(353)
CASH AND CASH EQUIVALENTS, END OF PERIOD	4,481	2,288	4,481	2,288
SUPPLEMENTAL CASH FLOW INFORMATION:
Cash paid for interest on long-term debt	13	6	37	17
Cash paid for income taxes (net of refunds)	86	19	179	45
Assets Held under Capital Leases
SUPPLEMENTAL CASH FLOW INFORMATION:
Property and equipment acquired	340	149	993	721
Assets Held under Build-To-Suit Leases
SUPPLEMENTAL CASH FLOW INFORMATION:
Property and equipment acquired	$ 150	$ 17	$ 163	$ 207