Acquisitions (Details) (Oakleaf [Member], USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011	Jul. 28, 2011
Adjustments to preliminary purchase price allocation
Accounts and other receivables	$ 71	$ 70
Other current assets	28	28
Property and equipment	70	72
Goodwill	328	327
Other intangible assets	87	87
Accounts payable	(82)	(82)
Accrued liabilities	(48)	(48)
Deferred income taxes, net	(9)	(10)
Other liabilities	(13)	(12)
Total purchase price	432	432	432
Adjustments [Member]
Adjustments to preliminary purchase price allocation
Accounts and other receivables	1
Property and equipment	(2)
Goodwill	1
Deferred income taxes, net	1
Other liabilities	$ (1)

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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The amount of acquisition cost of a business combination allocated to an identifiable intangible asset that will be amortized.

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The amount of acquisition cost of a business combination allocated to prepaid expenses and other current assets. Does not include amounts allocated to cash and cash equivalents, marketable securities, receivables, inventory, and assets not to be used.

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The amount of acquisition cost of a business combination allocated to accrued expenses of the acquired entity.

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Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

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The amount of acquisition cost of a business combination allocated to property, plant and equipment to be used in ongoing operations.

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