Business acquisitions earn-out compensation.

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Cash held subject to certain tax filings.

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Potential future earn out payments measurement period.

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Settlement assets and settlement liabilities holding period.

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

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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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No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled within one year or the normal operating cycle, if longer.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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- Definition

Total costs of sales and operating expenses for the period.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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 cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Acquisitions (Details Textual) $ in Thousands			12 Months Ended
Acquisitions (Details Textual) $ in Thousands	Sep. 30, 2018 USD ($)	Feb. 28, 2018 USD ($)	Dec. 31, 2018 USD ($) Segment	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Business Acquisition [Line Items]
Business acquisition, net of cash acquired			$ 144,791
Goodwill			$ 255,816	$ 210,080	$ 201,094
Number of reportable segments \| Segment			1
Revenues			$ 875,059	789,582	760,958
Operating expenses			$ 770,127	$ 683,897	$ 628,329
Software
Business Acquisition [Line Items]
Estimated useful life			51 months
Acquired client contracts
Business Acquisition [Line Items]
Estimated useful life			114 months
Minimum
Business Acquisition [Line Items]
Property and equipment depreciation period			3 years
Minimum \| Acquired client contracts
Business Acquisition [Line Items]
Estimated useful life			2 years
Maximum
Business Acquisition [Line Items]
Property and equipment depreciation period			10 years
Maximum \| Acquired client contracts
Business Acquisition [Line Items]
Estimated useful life			20 years
Business Ink
Business Acquisition [Line Items]
Business acquisition date			Feb. 28, 2018
Business acquisition, acquired equity percentage		100.00%
Business acquisition, net of cash acquired		$ 70,000
Goodwill		3,300
Intangible assets		$ 38,600
Forte Payment Systems, Inc
Business Acquisition [Line Items]
Business acquisition date			Oct. 01, 2018
Business acquisition, acquired equity percentage	100.00%
Business acquisition, net of cash acquired	$ 85,000
Goodwill	48,300
Intangible assets	34,400
Business acquisition, cash consideration	93,000
Cash held subject to certain tax filings	13,000
Potential future earn out payments	$ 18,800
Potential future earn out payments meassurement period	4 years
Accrued earn out payments			$ 1,300
Settlement assets and settlement liabilities holding period			Generally one to four business days depending on the payment model and contractual terms with the client.
Business Ink and Forte
Business Acquisition [Line Items]
Goodwill			$ 51,590
Revenues			74,000
Operating expenses			72,000
Business Ink and Forte \| SG&A
Business Acquisition [Line Items]
Business acquisition, transaction-related costs			3,600
Business acquisitions earn-out compensation			1,300
Business Ink and Forte \| Software
Business Acquisition [Line Items]
Intangible assets			10,354
Weighted-average life	7 years
Business Ink and Forte \| Acquired client contracts
Business Acquisition [Line Items]
Intangible assets			$ 63,570
Weighted-average life	11 years
Business Ink and Forte \| Minimum
Business Acquisition [Line Items]
Property and equipment depreciation period	1 year
Business Ink and Forte \| Minimum \| Software
Business Acquisition [Line Items]
Estimated useful life	4 years
Business Ink and Forte \| Minimum \| Acquired client contracts
Business Acquisition [Line Items]
Estimated useful life	4 months
Business Ink and Forte \| Maximum
Business Acquisition [Line Items]
Property and equipment depreciation period	8 years
Business Ink and Forte \| Maximum \| Software
Business Acquisition [Line Items]
Estimated useful life	8 years
Business Ink and Forte \| Maximum \| Acquired client contracts
Business Acquisition [Line Items]
Estimated useful life	15 years