Principal Contractual Commitments Excluding Open Orders for Inventory Purchases That Support Normal Operations (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2011 sqft
Long-term Purchase Commitment [Line Items]
Other commitments, tax contingencies	222
Occupied
Long-term Purchase Commitment [Line Items]
Corporate office space under build-to-suit leases	1,370,000
Under Development
Long-term Purchase Commitment [Line Items]
Corporate office space under build-to-suit leases	330,000