Goodwill and Other Intangible Assets - Goodwill (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Goodwill
Goodwill, Gross as of beginning of the year	$ 766,709	$ 764,310	$ 764,310
Goodwill, Accumulated Impairment	(567,967)		(567,967)	$ (567,967)
Goodwill, Net as of beginning of the year	198,742	196,343	196,343
Additions from acquisitions	30,112		2,399
Measurement period adjustments	(2,506)
Goodwill, Gross as of end of the year	794,315		766,709
Goodwill, Net as of end of the year	226,348		198,742
Measurement period adjustments related to acquisitions	2,200	300
Patient Care
Goodwill
Goodwill, Gross as of beginning of the year	627,410	625,011	625,011
Goodwill, Accumulated Impairment	(428,668)		(428,668)	(428,668)
Goodwill, Net as of beginning of the year	198,742	196,343	196,343
Additions from acquisitions	30,112		2,399
Measurement period adjustments	(2,506)
Goodwill, Gross as of end of the year	655,016		627,410
Goodwill, Net as of end of the year	226,348		198,742
Products & Services
Goodwill
Goodwill, Gross as of beginning of the year	139,299	$ 139,299	139,299
Goodwill, Accumulated Impairment	(139,299)		(139,299)	$ (139,299)
Goodwill, Gross as of end of the year	$ 139,299		$ 139,299