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Acquisitions - Additional Information (Details) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Nov. 01, 2014 USD ($) acquisition	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Business Acquisition [Line Items]
Goodwill		$ 421,760		$ 421,760		$ 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	151,265
Acquisition-related expenses		1,800		4,400
Medical Action Industries, Inc, ArcRoyal and Movianto
Business Acquisition [Line Items]
Acquisition-related expenses			$ 3,500		$ 4,100
International Segment
Business Acquisition [Line Items]
Goodwill		43,898		43,898		46,187
International Segment \| Medical Action Industries, Inc. and ArcRoyal
Business Acquisition [Line Items]
Goodwill	21,900
Domestic Segment
Business Acquisition [Line Items]
Goodwill		$ 377,862		$ 377,862		$ 377,089
Domestic Segment \| Medical Action Industries, Inc. and ArcRoyal
Business Acquisition [Line Items]
Goodwill	$ 129,400
Customer Relationships \| Medical Action Industries, Inc. and ArcRoyal
Business Acquisition [Line Items]
Acquired intangible assets, useful life	14 years