Amount of annual volume incentives provided to real estate franchisees

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Brand Marketing Fund Revenue

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Amount of domestic initial franchise fees and international area development fees.

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The number of offices.

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The total expense recognized in the period for promotion, public relations, and brand or product advertising.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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Amount of expense related to royalty payments under a contractual arrangement such as payment for mineral and drilling rights and use of technology or intellectual property.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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Franchising and Marketing Activities (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) franchisedandcompanyownedoffices	Dec. 31, 2019 USD ($) Countries franchisedandcompanyownedoffices	Dec. 31, 2018 USD ($) Countries franchisedandcompanyownedoffices	Dec. 31, 2020 Brokerage_Offices	Dec. 31, 2017 franchisedandcompanyownedoffices
Franchisor Disclosure [Line Items]
Initial franchise and area development fees \| $	$ 7	$ 9	$ 6
Annual volume incentives from Real Estate Franchisees \| $	63	50	52
Brand Marketing Fund Revenue \| $	$ 69	$ 90	$ 86
Franchised (domestic and international):
Franchisor Disclosure [Line Items]
Number of offices	19,386	17,776	15,830		14,039
Franchised (domestic and international): \| Century 21®
Franchisor Disclosure [Line Items]
Number of offices	13,222	11,640	9,637
Franchised (domestic and international): \| ERA®
Franchisor Disclosure [Line Items]
Number of offices	2,318	2,301	2,331
Franchised (domestic and international): \| Coldwell Banker®
Franchisor Disclosure [Line Items]
Number of offices	2,263	2,323	2,380
Franchised (domestic and international): \| Coldwell Banker Commercial®
Franchisor Disclosure [Line Items]
Number of offices	168	159	171
Franchised (domestic and international): \| Sotheby’s International Realty®
Franchisor Disclosure [Line Items]
Number of offices	952	962	949
Franchised (domestic and international): \| Better Homes and Gardens® Real Estate
Franchisor Disclosure [Line Items]
Number of offices	389	391	362
Franchised (domestic and international): \| Corcoran®
Franchisor Disclosure [Line Items]
Number of offices	74	0	0
Company owned:
Franchisor Disclosure [Line Items]
Royalty expense \| $	$ (306)	$ (282)	$ (295)
Marketing and Advertising Expense \| $	$ (10)	$ (11)	$ (11)
Number of offices	673	713	755	670	789
Company owned: \| Coldwell Banker®
Franchisor Disclosure [Line Items]
Number of offices	605	634	672
Company owned: \| Sotheby’s International Realty®
Franchisor Disclosure [Line Items]
Number of offices	39	37	41
Company owned: \| Corcoran®
Franchisor Disclosure [Line Items]
Number of offices	29	42	42