Segment information - Reportable Segments Revenue and Adjusted EBITDA (Detail) (USD $)	3 Months Ended				6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Sales Information [Line Items]
Consolidated revenue	$ 42,299,000	[1]	$ 39,241,000	[1]	$ 84,179,000	[1]	$ 78,316,000	[1]
Operating Segments | Real Estate Franchise Services
Sales Information [Line Items]
Consolidated revenue	38,699,000	[1]	34,884,000	[1]	77,798,000	[1]	70,534,000	[1]
Operating Segments | Brokerage
Sales Information [Line Items]
Consolidated revenue	$ 3,600,000	[1]	$ 4,357,000	[1]	$ 6,381,000	[1]	$ 7,782,000	[1]

[1] Transactions between the Real Estate Franchise Services and the Brokerages reportable segments are eliminated in consolidation. Revenues for the Real Estate Franchise Services reportable segment include intercompany amounts paid from the Company’s brokerage services business of $463,000 and $393,000 for the three months ended June 30, 2014 and 2013, respectively, and $885,000 and $746,000 for the six months ended June 30, 2014 and 2013, respectively. Such amounts are eliminated in the Brokerages reportable segment