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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

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- Definition

The amount of cash and cash equivalents acquired in a business combination.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 52

-Subparagraph c

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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Acquisitions.

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Net loss recognized by acquiree post acquisition date.

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Revenue recognized.

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Acquisition of Oakleaf Global Holdings (Details Textual) (USD $) In Millions	3 Months Ended		9 Months Ended			3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Jul. 28, 2011	Sep. 30, 2011 Oakleaf [Member]	Sep. 30, 2011 Oakleaf [Member]	Dec. 31, 2010 Oakleaf [Member]	Jul. 28, 2011 Oakleaf [Member]
Acquisitions (Textual) [Abstract]
Acquisition cost of acquired entity					$ 432				$ 432
Cash received in acquisition									4
Operating revenues	3,522	3,235	9,972	9,328				580
Acquisition-related costs classified as Selling, general and administrative expenses						1	1
Revenues recognized by acquiree post the acquisition date							112
Net loss recognized by acquiree post the acquisition date							less than $1 million
Goodwill calculated as the excess of the consideration					$ 320				$ 320