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Percentage of voting equity interests acquired in the business combination.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

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-Paragraph 2

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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.

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Amount of acquisition cost of a business combination allocated to assets, excluding financial assets and goodwill, lacking physical substance.

+ References

No definition available.

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- Definition

The amount of acquisition cost of a business combination allocated to the noncurrent portion of the long-term debt assumed from the acquired entity.

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-Publisher FASB

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- Definition

This element represents the fair value of the noncontrolling interest in the acquiree at the acquisition date.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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No definition available.

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The number of businesses acquired by the entity during the 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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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

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Business Acquisitions (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Business Acquisition [Line Items]
Acquisitions, net of cash acquired	$ 591	$ 0	$ 0
Goodwill amount acquired	112
Intangible franchise contracts acquired	92
Long-term debt acquired	590
Residential real estate brokerage franchise business [Member]
Business Acquisition [Line Items]
Business acquisition, percentage of voting interests acquired	66.70%
Redeemable noncontrolling interest carrying amount	$ 65
Residential real estate brokerage business [Member]
Business Acquisition [Line Items]
Real estate brokerage businesses purchased	5
Noncontrolling interest put option [Member] \| Residential real estate brokerage franchise business [Member]
Business Acquisition [Line Items]
Noncontrolling ownership percentage by third parties	33.30%
Noncontrolling interest call option [Member] \| Residential real estate brokerage franchise business [Member]
Business Acquisition [Line Items]
Noncontrolling ownership percentage by third parties	33.30%