Amount of increase in other assets (current and noncurrent), resulting from a business combination.

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Amount of increase in other liabilities (current and noncurrent), resulting from a business combination.

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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
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-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6405-128476

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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No definition available.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Amount of increase in assets, excluding financial assets and goodwill, lacking physical substance with an indefinite life, from an acquisition.

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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 business during the period. The cash portion only of the acquisition price.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 13
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Acquisitions (Details) £ in Millions, $ in Millions	6 Months Ended		12 Months Ended
Acquisitions (Details) £ in Millions, $ in Millions	Jun. 30, 2017 GBP (£) real_estate_brokerage_operations	Jun. 30, 2017 USD ($) real_estate_brokerage_operations	Dec. 31, 2016 USD ($) real_estate_brokerage_operations
Business Acquisition [Line Items]
Goodwill acquired		$ 4
Company Owned Brokerage Services
Business Acquisition [Line Items]
Goodwill acquired		4
Title and Settlement Services
Business Acquisition [Line Items]
Goodwill acquired		$ 0
NRT Business Combinations [Member] \| Company Owned Brokerage Services
Business Acquisition [Line Items]
Number of business acquired (in real estate brokerage related operations) \| real_estate_brokerage_operations	7	7	11
Cash consideration paid for acquisition	£ 4		$ 74
Goodwill acquired		$ 3	52
Liabilities established related to contingent consideration			9
Other assets acquired			5
Other liabilities acquired			3
NRT Business Combinations [Member] \| Customer relationships \| Company Owned Brokerage Services
Business Acquisition [Line Items]
Finite-lived intangible assets acquired			20
NRT Business Combinations [Member] \| Pendings and listings \| Company Owned Brokerage Services
Business Acquisition [Line Items]
Finite-lived intangible assets acquired			6
NRT Business Combinations [Member] \| Other intangible assets \| Company Owned Brokerage Services
Business Acquisition [Line Items]
Finite-lived intangible assets acquired		$ 1	$ 3
TRG Business Combinations [Member] \| Title and Settlement Services
Business Acquisition [Line Items]
Number of business acquired (in real estate brokerage related operations) \| real_estate_brokerage_operations			1
Cash consideration paid for acquisition			$ 24
Goodwill acquired			20
Liabilities established related to contingent consideration			10
Other assets acquired			6
Other liabilities acquired			9
TRG Business Combinations [Member] \| Indefinite life—Trademarks (b) \| Title and Settlement Services
Business Acquisition [Line Items]
Indefinite-lived intangible assets acquired			3
TRG Business Combinations [Member] \| Indefinite life—Title plant shares (e) \| Title and Settlement Services
Business Acquisition [Line Items]
Indefinite-lived intangible assets acquired			7
TRG Business Combinations [Member] \| Pendings and listings \| Title and Settlement Services
Business Acquisition [Line Items]
Finite-lived intangible assets acquired			5
TRG Business Combinations [Member] \| Other intangible assets \| Title and Settlement Services
Business Acquisition [Line Items]
Finite-lived intangible assets acquired			$ 2