Non-controlling Interest - Net income reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Minority Interest [Line Items]
Weighted average ownership percentage of controlling interest									58.48%	58.40%	42.33%
Weighted average ownership percentage of noncontrolling interest									41.52%	41.60%	57.67%
Total (as a percentage)									100.00%	100.00%	100.00%
Income before provision for income taxes attributable to RE/MAX Holdings, Inc.									$ 66,599	$ 36,446	$ 26,554
Provision for income taxes attributable to RE/MAX Holdings, Inc.									(53,784)	(14,050)	(10,142)
Net income attributable to RE/MAX Holdings, Inc.	$ (3,461)	$ 3,835	$ 7,529	$ 4,912	$ 3,857	$ 6,786	$ 6,814	$ 4,939	12,815	22,396	16,412
Income before provision for income taxes: Non-controlling interest									24,156	26,053	36,251
Provision for income taxes: Non-controlling interest									(1,792)	(1,223)	(1,888)
Net income: Non-controlling interest	5,395	3,702	8,108	5,159	4,540	7,520	7,314	5,456	22,364	24,830	34,363
Income before provision for income taxes	46,627	10,628	20,399	13,101	11,494	18,938	18,413	13,654	90,755	62,499	62,805
Provision for income taxes	(44,693)	(3,091)	(4,762)	(3,030)	(3,097)	(4,632)	(4,285)	(3,259)	(55,576)	(15,273)	(12,030)
Net income	$ 1,934	$ 7,537	$ 15,637	$ 10,071	$ 8,397	$ 14,306	$ 14,128	$ 10,395	35,179	47,226	50,775
Non-controlling interest
Minority Interest [Line Items]
Net income									$ 22,364	$ 24,830	$ 34,363