Quarterly Financial Information (Unaudited) - Narrative (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	Jun. 30, 2016	Mar. 31, 2016	Sep. 30, 2014	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Restructuring Expenses	$ 3,400	$ 800	$ 13,500	$ 300	$ 15,500			$ 4,700	$ 17,994	$ 20,218	$ 0
Non-cash provisional income tax benefit	137,000
Remeasurement of net deferred tax liabilities	140,000
Estimated expense from loss of manufacturing deduction and other	$ 3,000
Retirement benefits expense							$ 3,700
Building | Other Segments | Operating Segments
Business Acquisition [Line Items]
Gain on sale of corporate office building							11,100
Disposal Group, Disposed of by Sale, Not Discontinued Operations | HomeSmart
Business Acquisition [Line Items]
Charge related to write down of disposal group							$ 4,600
Impairment of long-lived assets to be disposed of						$ 1,000				$ 1,100