Segment Information - Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Segment Reporting Information
Total revenue	$ 85,401	$ 91,004
Real Estate
Segment Reporting Information
Total revenue	60,630	64,737
Mortgage
Segment Reporting Information
Total revenue	3,188	3,028
Marketing Funds fees
Segment Reporting Information
Total revenue	21,342	22,851
Other.
Segment Reporting Information
Total revenue	241	388
Continuing franchise fees
Segment Reporting Information
Total revenue	32,076	33,499
Continuing franchise fees | Real Estate
Segment Reporting Information
Total revenue	29,547	31,120
Continuing franchise fees | Mortgage
Segment Reporting Information
Total revenue	2,529	2,379
Annual dues
Segment Reporting Information
Total revenue	8,618	8,920
Annual dues | Real Estate
Segment Reporting Information
Total revenue	8,618	8,920
Broker fees
Segment Reporting Information
Total revenue	10,892	15,085
Broker fees | Real Estate
Segment Reporting Information
Total revenue	10,892	15,085
Franchise sales and other revenue
Segment Reporting Information
Total revenue	12,473	10,649
Franchise sales and other revenue | Real Estate
Segment Reporting Information
Total revenue	11,573	9,612
Franchise sales and other revenue | Mortgage
Segment Reporting Information
Total revenue	$ 659	$ 649