Segment Information - Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Segment Reporting Information
Total revenue	$ 82,447	$ 92,172	$ 167,848	$ 183,176
Real Estate
Segment Reporting Information
Total revenue	57,559	65,776	118,189	130,513
Mortgage
Segment Reporting Information
Total revenue	3,616	3,115	6,804	6,143
Marketing Funds fees
Segment Reporting Information
Total revenue	21,077	22,909	42,419	45,760
Other.
Segment Reporting Information
Total revenue	195	372	436	760
Continuing franchise fees
Segment Reporting Information
Total revenue	32,101	34,128	64,177	67,627
Continuing franchise fees | Real Estate
Segment Reporting Information
Total revenue	29,387	31,619	58,934	62,739
Continuing franchise fees | Mortgage
Segment Reporting Information
Total revenue	2,714	2,509	5,243	4,888
Annual dues
Segment Reporting Information
Total revenue	8,587	9,016	17,205	17,936
Annual dues | Real Estate
Segment Reporting Information
Total revenue	8,587	9,016	17,205	17,936
Broker fees
Segment Reporting Information
Total revenue	14,321	19,317	25,213	34,402
Broker fees | Real Estate
Segment Reporting Information
Total revenue	14,321	19,317	25,213	34,402
Franchise sales and other revenue
Segment Reporting Information
Total revenue	6,361	6,802	18,834	17,451
Franchise sales and other revenue | Real Estate
Segment Reporting Information
Total revenue	5,264	5,824	16,837	15,436
Franchise sales and other revenue | Mortgage
Segment Reporting Information
Total revenue	$ 902	$ 606	$ 1,561	$ 1,255