BUSINESS SEGMENT INFORMATION (segment results) (Details) $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2020 USD ($) customers	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2021 USD ($) segment customers	Dec. 31, 2020 USD ($) customers	Dec. 31, 2019 USD ($) customers
Business segment information [Line Items]
Number of reportable segments | segment					4
Revenue	$ 454,492	$ 439,461	$ 410,405	$ 486,423	$ 2,022,197	$ 1,790,781	$ 2,008,715
Depreciation and amortization					(148,767)	(110,792)	(126,036)
Interest expense					(55,554)	(23,140)	(34,682)
Net income attributable to non-controlling Interest					139	91	0
Asset impairment charges					0	(101,749)	(421,090)
Restructuring, integration and other costs					(58,947)	(80,665)	(79,511)
CEO transition costs					0	30	(9,390)	[1]
Share-based compensation expense					(29,477)	(21,824)	(19,702)
Share-based compensation expense							(19,138)
Acquisition transaction costs					(18,913)	(8)	(215)
Certain legal-related (expense) benefit					(2,443)	2,164	(6,420)
Loss on sales of businesses and customer lists					0	(1,846)	(124)
Income (loss) before income taxes					93,803	26,803	(215,740)
Reportable business segments [Member]
Business segment information [Line Items]
Adjusted EBITDA					585,356	538,022	655,538
Reportable business segments [Member] | Payments [Member]
Business segment information [Line Items]
Revenue					510,359	301,901	269,573
Adjusted EBITDA					105,576	68,117	74,384
Reportable business segments [Member] | Cloud Solutions [Member]
Business segment information [Line Items]
Revenue					262,310	252,773	318,383
Adjusted EBITDA					70,172	61,580	77,199
Reportable business segments [Member] | Promotional Solutions [Member]
Business segment information [Line Items]
Revenue					546,473	529,649	640,892
Adjusted EBITDA					85,384	66,620	101,293
Reportable business segments [Member] | Checks [Member]
Business segment information [Line Items]
Revenue					703,055	706,458	779,867
Adjusted EBITDA					324,224	341,705	402,662
Corporate operations [Member]
Business segment information [Line Items]
Adjusted EBITDA					$ (177,591)	$ (173,480)	$ (174,672)
Customer concentration risk [Member]
Business segment information [Line Items]
Number of customers | customers	0				0	0	0
Customer concentration risk [Member] | Total revenue benchmark [Member] | Major customers [Member]
Business segment information [Line Items]
Concentration risk, percentage					10.00%	10.00%	10.00%

[1] In 2019, CEO transition costs includes share-based compensation expense related to the modification of certain awards in conjunction with our CEO transition (Note 9).