Segment information - Reportable Segments Revenue and Adjusted EBITDA (Parenthetical) (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
Segment Reporting Information [Line Items]
Total segment reporting revenues	$ (44,207,000)	[1]	$ (41,880,000)	[1]
Intersegment Eliminations
Segment Reporting Information [Line Items]
Total segment reporting revenues	$ 432,000		$ 422,000

[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 $432,000 and $422,000 for the three months ended March 31, 2015 and 2014, respectively. Such amounts are eliminated in the Brokerages reportable segment