Goodwill and Other Intangible Assets (Finite-lived Intangible Assets) (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Amortized Intangible Assets [Line Items]
Asset Impairment Charges	$ 0	$ 8,109	$ 0	$ 0	$ 78	$ 312	$ 9,224	$ 0	$ 8,109	$ 9,614	$ 1,603
Amortization of Intangible Assets
Amortization of intangible assets	13,362	12,269	$ 11,399	$ 10,384	$ 12,897	$ 10,923	$ 10,531	$ 6,836	47,414	$ 41,187	$ 26,671
Estimated amortization of intangible assets, 2019	52,000								52,000
Estimated amortization of intangible assets, 2020	49,000								49,000
Estimated amortization of intangible assets, 2021	43,000								43,000
Estimated amortization of intangible assets, 2022	37,000								37,000
Estimated amortization of intangible assets, 2023	29,000								29,000
Estimated amortization of intangible assets, after 2023	$ 53,000								$ 53,000
Graham Healthcare Group [Member]
Amortized Intangible Assets [Line Items]
Impairment of intangible assets		$ 7,900