Summary of Significant Accounting Policies - Additional Information (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2016 USD ($) item	Dec. 31, 2016 USD ($) segment country	Dec. 31, 2015 USD ($) segment	Dec. 31, 2014 USD ($)	Oct. 07, 2013
Significant Accounting Policies [Line Items]
Number of reportable segments | segment		1	2
Number of brokerages having assets and liabilities sold | item	21
Franchise revenue recognized		$ 25,131,000	$ 25,468,000	$ 23,440,000
Deferred revenue, additions		1,012,000	930,000
Recognized revenue		$ 329,000	472,000	484,000
Number of countries and territories operations conducted | country		100
Impairment of franchise agreements and other intangible assets subject to amortization		$ 0	0	0
Impairment of goodwill		0	0	0
Investments in equity method investees		$ 0	0
Equity-based compensation vesting period		3 years
Cumulative effect adjustment from change in accounting principle		$ 28,000
Increase in cash flows provided by operating activities		64,379,000	77,358,000	64,445,000
Net increase in cash flows used in financing activities		228,000	(75,186,000)	(43,413,000)
Income tax benefit		261,000	2,770,000	736,000
Deferred tax assets, net		105,637,000	109,245,000
Debt issuance costs, net			1,527,000
Early adoption of accounting pronouncement
Significant Accounting Policies [Line Items]
Cumulative effect adjustment from change in accounting principle	$ 44,000
Increase in cash flows provided by operating activities			2,770,000	736,000
Net increase in cash flows used in financing activities			$ (2,770,000)	(736,000)
Income tax benefit		$ 261,000
Deferred tax assets, net	$ 3,332,000
Residential mortgage operation
Significant Accounting Policies [Line Items]
Equity method investment, ownership percentage			50.00%
Software and Software Development Costs | Minimum
Significant Accounting Policies [Line Items]
Useful life of intangible assets		3 years
Software and Software Development Costs | Maximum
Significant Accounting Policies [Line Items]
Useful life of intangible assets		5 years
Accounts Receivable | Prime plus
Significant Accounting Policies [Line Items]
Accounts and notes receivable interest rate percentage		2.00%
Franchise Agreements
Significant Accounting Policies [Line Items]
Franchise revenue recognized		$ 8,825,000	$ 9,697,000	$ 8,965,000
RMCO, LLC
Significant Accounting Policies [Line Items]
Parent economic interest in RMCO (as a percent)		58.43%	58.33%		39.56%