Segment Information - Operating Segment Results (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) segment	Sep. 30, 2016 USD ($)
Segment information
Number of reportable segments \| segment			2
Net Revenue	$ 174,188	$ 156,241	$ 501,932	$ 457,250
Operating Income	41,042	24,155	115,120	92,331
Healthcare
Segment information
Net Revenue	156,219	138,470	447,581	403,643
Operating Income	38,094	22,544	107,944	85,879
Global Retail and Other
Segment information
Net Revenue	17,969	17,771	54,351	53,607
Operating Income	$ 2,948	$ 1,611	$ 7,176	$ 6,452

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The net result for the period of deducting operating expenses from operating revenues.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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