Goodwill and Other Intangible Assets - Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Schedule of Finite and Indefinite-Lived Intangible Assets [Line Items]
Accumulated Amortization	$ (160,634)	$ (155,659)
Net Carrying Amount	181,582
Gross carrying amount	387,416	388,019
Total acquired intangible assets	226,782	232,360
Trade names
Schedule of Finite and Indefinite-Lived Intangible Assets [Line Items]
Trade name (Indefinite lived)	$ 45,200	45,200
Facility management contracts
Schedule of Finite and Indefinite-Lived Intangible Assets [Line Items]
Weighted Average Useful Life	16 years 3 months
Gross Carrying Amount	$ 308,516	308,419
Accumulated Amortization	(132,753)	(127,481)
Net Carrying Amount	$ 175,763	180,938
Covenants not to compete
Schedule of Finite and Indefinite-Lived Intangible Assets [Line Items]
Weighted Average Useful Life	1 year
Gross Carrying Amount	$ 0	700
Accumulated Amortization	0	(700)
Net Carrying Amount	$ 0	0
Technology
Schedule of Finite and Indefinite-Lived Intangible Assets [Line Items]
Weighted Average Useful Life	7 years 3 months
Gross Carrying Amount	$ 33,700	33,700
Accumulated Amortization	(27,881)	(27,478)
Net Carrying Amount	$ 5,819	$ 6,222