Note 5. Franchising and Marketing Activities Franchising and Marketing Activities (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($) franchisedandcompanyownedoffices	Dec. 31, 2015 USD ($) franchisedandcompanyownedoffices	Dec. 31, 2014 USD ($) franchisedandcompanyownedoffices	Dec. 31, 2016 Brokerage_Offices	Dec. 31, 2013 franchisedandcompanyownedoffices
Franchisor Disclosure [Line Items]
Initial franchise and area development fees | $	$ 8	$ 8	$ 9
Annual volume incentives from Real Estate Franchisees | $	$ 56	$ 51	$ 50
Franchised:
Franchisor Disclosure [Line Items]
Number of offices	13,314	12,771	12,769		13,032
Franchised: | Century 21®
Franchisor Disclosure [Line Items]
Number of offices	7,330	6,897	6,902
Franchised: | ERA®
Franchisor Disclosure [Line Items]
Number of offices	2,347	2,355	2,304
Franchised: | Coldwell Banker®
Franchisor Disclosure [Line Items]
Number of offices	2,289	2,258	2,396
Franchised: | Coldwell Banker Commercial®
Franchisor Disclosure [Line Items]
Number of offices	180	163	167
Franchised: | Sotheby’s International Realty®
Franchisor Disclosure [Line Items]
Number of offices	836	794	717
Franchised: | Better Homes and Gardens® Real Estate
Franchisor Disclosure [Line Items]
Number of offices	332	304	283
Company Owned:
Franchisor Disclosure [Line Items]
Royalty expense | $	$ 282	$ 284	$ 269
Number of offices	789	787	727	790	706
Marketing and Advertising Expense | $	$ 11	$ 11	$ 14
Company Owned: | ERA®
Franchisor Disclosure [Line Items]
Number of offices	0	0	0
Company Owned: | Coldwell Banker®
Franchisor Disclosure [Line Items]
Number of offices	708	708	651
Company Owned: | Sotheby’s International Realty®
Franchisor Disclosure [Line Items]
Number of offices	41	41	39
Company Owned: | Corcoran Other [Member]
Franchisor Disclosure [Line Items]
Number of offices	40	38	37