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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of liability recognized arising from contingent consideration in a business combination.

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This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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Acquisitions - Additional Information (Detail) In Millions, unless otherwise specified	3 Months Ended		0 Months Ended	3 Months Ended	0 Months Ended
	Mar. 31, 2014 USD ($)	Mar. 31, 2013 USD ($)	Jan. 31, 2013 Greenstar LLC [Member] USD ($)	Mar. 31, 2013 Greenstar LLC [Member] USD ($)	Jul. 05, 2013 RCI Environnment Inc [Member] USD ($)	Jul. 05, 2013 RCI Environnment Inc [Member] CAD	Mar. 31, 2014 RCI Environnment Inc [Member] USD ($)
Business Acquisition [Line Items]
Acquisition cost of acquired entity	$ 11	$ 180	$ 170		$ 481	509
Additional consideration payable			40
Estimated fair value of liability for additional cash payments related to acquisitions			16
Revenues recognized by acquiree				25
Net loss recognized by acquiree				3
Purchase price allocation to goodwill			122				191
Total consideration, net of cash acquired, for business acquisitions closed during the year					$ 487	515