Principal Contractual Commitments Excluding Open Orders for Inventory Purchases That Support Normal Operations (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Long-term Purchase Commitment [Line Items]
Other commitments, tax contingencies	$ 294

Tax contingencies for which a reasonably reliable estimate of the amount and period of payment cannot be made.

No definition available.

Name:	amzn_UnrecognizedTaxBenefitsUncertainAmounts
Namespace Prefix:	amzn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant