Basis and Summary of Significant Accounting Policies - Assets Held for Sale (Details) $ in Thousands			9 Months Ended
	May 13, 2016 USD ($) Store	Jan. 29, 2016 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Significant Accounting Policies [Line Items]
Assets Held for Sale			$ 11,925		$ 8,866
Proceeds from divestiture of businesses			$ 1,130	$ 36,295
Proceeds from sales of building		$ 13,600
Disposal Group, Held-for-sale, Not Discontinued Operations | HomeSmart
Significant Accounting Policies [Line Items]
Disposal group, number of stores | Store	82
Proceeds from divestiture of businesses	$ 35,000
Loss on disposal				4,200
Business exit costs				1,400
Building | Other operating expense (income), net
Significant Accounting Policies [Line Items]
Gain on sale of corporate office building				$ 11,100