SEGMENT INFORMATION (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Nov. 30, 2016	Nov. 30, 2015	Nov. 30, 2016	Nov. 30, 2015
Segment Reporting Information [Line Items]
Revenues	$ 941,821	$ 722,350	$ 1,881,313	$ 1,471,146
Operating income (loss) for segments	105,267	123,165	226,373	260,937
Depreciation and amortization	108,682	38,749	211,869	77,506
Corporate
Segment Reporting Information [Line Items]
Operating income (loss) for segments	(78,012)	(29,825)	(142,167)	(60,532)
Depreciation and amortization	1,054	1,248	2,486	2,861
North America \| North America \| Operating segments
Segment Reporting Information [Line Items]
Revenues	701,300	511,335	1,413,064	1,042,192
Operating income (loss) for segments	105,746	79,121	211,446	162,635
Depreciation and amortization	90,964	24,222	177,880	47,965
Europe \| Europe \| Operating segments
Segment Reporting Information [Line Items]
Revenues	174,904	158,016	344,469	326,373
Operating income (loss) for segments	60,875	62,012	126,414	134,745
Depreciation and amortization	12,188	9,921	22,601	20,265
Asia-Pacific \| Asia-Pacific \| Operating segments
Segment Reporting Information [Line Items]
Revenues	65,617	52,999	123,780	102,581
Operating income (loss) for segments	16,658	11,857	30,680	24,089
Depreciation and amortization	4,476	$ 3,358	8,902	$ 6,415
Heartland Payment Systems, Inc
Segment Reporting Information [Line Items]
Acquisition related costs	$ 36,600		$ 67,200

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=73531572&loc=d3e1043-128460

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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+ 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)
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