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Acquisitions - Additional Information (Details) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Nov. 01, 2014 USD ($) acquisition	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Business Acquisition [Line Items]
Goodwill		$ 420,772		$ 420,772		$ 423,276
Medical Action Industries, Inc. and ArcRoyal
Business Acquisition [Line Items]
Number of businesses acquired \| acquisition	2
Combined consideration, net of cash acquired	$ 261,600
Capitalized lease obligations assumed	13,400
Goodwill	$ 150,613
Acquisition related costs		1,300		5,500
Medical Action Industries, Inc, ArcRoyal and Movianto
Business Acquisition [Line Items]
Acquisition related costs			$ 4,600		$ 8,700
Customer Relationships \| Medical Action Industries, Inc. and ArcRoyal
Business Acquisition [Line Items]
Acquired intangible assets, useful life	14 years
International Segment
Business Acquisition [Line Items]
Goodwill		42,574		42,574		46,187
International Segment \| Medical Action Industries, Inc. and ArcRoyal
Business Acquisition [Line Items]
Goodwill	$ 20,900
Domestic Segment
Business Acquisition [Line Items]
Goodwill		$ 378,198		$ 378,198		$ 377,089
Domestic Segment \| Medical Action Industries, Inc. and ArcRoyal
Business Acquisition [Line Items]
Goodwill	$ 129,700