Goodwill and Other Intangible Assets - Changes In Goodwill (Details) - USD ($)	9 Months Ended
Sep. 30, 2016	Dec. 31, 2015
Goodwill [Roll Forward]
Gross goodwill, Beginning of the period	$ 1,124,225,000
Acquisition of EFS	718,979,000
Acquisition adjustments	502,000
Impact of foreign currency translation	9,827,000
Gross goodwill, End of period	1,853,533,000
Accumulated impairment, Beginning of the period	(11,347,000)
Impact of foreign currency translation	(523,000)
Accumulated impairment, End of period	(11,870,000)
Net goodwill	1,841,663,000	$ 1,112,878,000
Goodwill impairment	0
Fleet Solutions Segment
Goodwill [Roll Forward]
Gross goodwill, Beginning of the period	735,770,000
Acquisition of EFS	602,423,000
Acquisition adjustments	0
Impact of foreign currency translation	8,617,000
Gross goodwill, End of period	1,346,810,000
Accumulated impairment, Beginning of the period	(867,000)
Impact of foreign currency translation	(40,000)
Accumulated impairment, End of period	(907,000)
Net goodwill	1,345,903,000	734,903,000
Travel and Corporate Solutions Segment
Goodwill [Roll Forward]
Gross goodwill, Beginning of the period	38,134,000
Acquisition of EFS	116,556,000
Acquisition adjustments	0
Impact of foreign currency translation	(1,739,000)
Gross goodwill, End of period	152,951,000
Accumulated impairment, Beginning of the period	(10,480,000)
Impact of foreign currency translation	(483,000)
Accumulated impairment, End of period	(10,963,000)
Net goodwill	141,988,000	27,654,000
Health and Employee Benefit Solutions Segment
Goodwill [Roll Forward]
Gross goodwill, Beginning of the period	350,321,000
Acquisition of EFS	0
Acquisition adjustments	502,000
Impact of foreign currency translation	2,949,000
Gross goodwill, End of period	353,772,000
Accumulated impairment, Beginning of the period	0
Impact of foreign currency translation	0
Accumulated impairment, End of period	0
Net goodwill	$ 353,772,000	$ 350,321,000

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of accumulated impairment loss for 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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The amount of an adjustment to a previously reported goodwill impairment charge, which will be recognized in the subsequent reporting period.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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