Significant Risks and Uncertainties	12 Months Ended
Significant Risks and Uncertainties	Dec. 31, 2014
Risks and Uncertainties [Abstract]
Significant Risks and Uncertainties	Significant Risks and Uncertainties Many of our hospital customers in the U.S. are represented by group purchasing organizations (GPOs) that contract with us for services on behalf of the GPO members. GPOs representing a significant portion of our business are Novation, LLC (Novation), MedAssets Inc. (MedAssets) and Premier, Inc. (Premier). Members of these GPOs have incentives to purchase from their primary selected distributor; however, they operate independently and are free to negotiate directly with distributors and manufacturers. For 2014, 2013 and 2012, net revenue from hospitals under contract with these GPOs represented the following approximate percentages of our net revenue annually: Novation—33%; MedAssets (including Broadlane in 2012)—24% to 25%; and Premier—21% to 24%. Net revenue from sales of product supplied by subsidiaries of Covidien Ltd. and Johnson & Johnson Healthcare Systems, Inc. represented between approximately 13% to 14% and 9% to 10% of our net revenue annually for 2014, 2013 and 2012, respectively.

The entire disclosure for any concentrations existing at the date of the financial statements that make an entity vulnerable to a reasonably possible, near-term, severe impact. This disclosure informs financial statement users about the general nature of the risk associated with the concentration, and may indicate the percentage of concentration risk as of the balance sheet date.

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