Goodwill and Other Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Goodwill
Balance at the beginning of the period			$ 343,766
Acquisitions			2,358
Balance at the end of the period	$ 346,124		346,124
Other intangible assets
Cost	153,297		153,297		$ 150,105
Accumulated Amortization	(129,097)		(129,097)		(123,834)
Total	24,200		24,200		26,271
Cost	319,297		319,297		316,105
Accumulated Impairment	(34,900)		(34,900)		(34,900)
Net	155,300		155,300		157,371
Total amortization expense	2,300	$ 2,800	5,300	$ 5,800
Trade names
Other intangible assets
Cost	166,000		166,000		166,000
Net	131,100		131,100		131,100
Accumulated Impairment	(34,900)		(34,900)		(34,900)
Customer relationship
Other intangible assets
Cost	125,031		125,031		122,109
Accumulated Amortization	(101,942)		(101,942)		(97,704)
Total	23,089		23,089		24,405
Supply agreement
Other intangible assets
Cost	26,000		26,000		26,000
Accumulated Amortization	(26,000)		(26,000)		(25,274)
Total					726
Non-compete agreements
Other intangible assets
Cost	2,028		2,028		1,758
Accumulated Amortization	(1,016)		(1,016)		(856)
Total	1,012		1,012		902
Trade names
Other intangible assets
Cost	238		238		238
Accumulated Amortization	(139)		(139)
Total	99		99		$ 238
Medical Equipment Solutions
Goodwill
Balance at the beginning of the period			227,486
Balance at the end of the period	227,486		227,486
Clinical Engineering Solutions
Goodwill
Balance at the beginning of the period			62,826
Acquisitions			214
Balance at the end of the period	63,040		63,040
Surgical Services
Goodwill
Balance at the beginning of the period			53,454
Acquisitions			2,144
Balance at the end of the period	$ 55,598		$ 55,598