General - Concentration of Business (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Concentration of Business
Net revenue	$ 1,305,623	$ 1,117,022
Minimum
Concentration of Business
Term of Contract	1 year
Term of renewed contract	1 year
Notice period for termination of contract	60 days
Maximum
Concentration of Business
Term of Contract	3 years
Term of renewed contract	2 years
Notice period for termination of contract	180 days
CMS
Concentration of Business
Net revenue	$ 111,600	50,300
Pennsylvania Counties
Concentration of Business
Net revenue	109,900	110,000
Agencies and departments of the United States federal government
Concentration of Business
Net revenue	$ 88,000	$ 42,500

Represents the notice period required for termination of contract.

No definition available.

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- Definition

Represents the term of the contract entered with the customer.

+ References

No definition available.

+ Details

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- Definition

Represents the term of the renewed contract with the customer.

+ References

No definition available.

+ Details

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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.

+ References

No definition available.

+ Details

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- Definition

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

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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