Segment information - Capital Expenditures, Depreciation, Amortization (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Capital Expenditures by Business Segment	$ 39.9	$ 26.0	$ 20.9	$ 14.3	$ 53.7	$ 26.3	$ 32.3	$ 23.8	$ 101.1	$ 136.1	$ 172.9
Depreciation									135.7	156.4	159.4
Amortization of intangible assets									4.2	5.5	6.4
Total	$ 33.6	$ 33.1	$ 36.5	$ 36.7	$ 39.4	$ 39.7	$ 40.9	$ 41.9	139.9	161.9	165.8
Business segments
Segment Reporting Information [Line Items]
Capital Expenditures by Business Segment									89.8	114.2	134.1
Depreciation									120.5	137.2	144.0
Business segments | U.S.
Segment Reporting Information [Line Items]
Capital Expenditures by Business Segment									21.7	31.1	42.4
Depreciation									47.6	49.8	49.1
Amortization of intangible assets									0.0	0.0	0.2
Business segments | France
Segment Reporting Information [Line Items]
Capital Expenditures by Business Segment									16.0	17.9	13.8
Depreciation									15.5	19.3	22.1
Amortization of intangible assets									0.2	0.3	0.4
Business segments | Mexico
Segment Reporting Information [Line Items]
Capital Expenditures by Business Segment									9.3	13.3	24.5
Depreciation									14.4	19.6	19.2
Business segments | Brazil
Segment Reporting Information [Line Items]
Capital Expenditures by Business Segment									6.2	14.7	13.2
Depreciation									7.6	8.8	9.0
Amortization of intangible assets									1.2	1.4	1.7
Business segments | Canada
Segment Reporting Information [Line Items]
Capital Expenditures by Business Segment									6.1	6.4	9.6
Depreciation									8.1	8.5	8.3
Business segments | Latin America
Segment Reporting Information [Line Items]
Capital Expenditures by Business Segment									13.5	17.0	17.8
Depreciation									10.0	12.2	13.5
Amortization of intangible assets									0.3	0.3	0.4
Business segments | EMEA
Segment Reporting Information [Line Items]
Capital Expenditures by Business Segment									11.1	9.4	8.9
Depreciation									11.5	13.6	16.9
Amortization of intangible assets									0.6	1.1	1.2
Business segments | Asia
Segment Reporting Information [Line Items]
Capital Expenditures by Business Segment									4.2	3.6	2.4
Depreciation									3.9	3.2	3.7
Amortization of intangible assets									0.9	0.9	1.0
Business segments | Payment Services
Segment Reporting Information [Line Items]
Capital Expenditures by Business Segment									1.7	0.8	1.5
Depreciation									1.9	2.2	2.2
Amortization of intangible assets									1.0	1.5	1.5
Corporate items
Segment Reporting Information [Line Items]
Capital Expenditures by Business Segment									7.0	16.5	29.8
Depreciation									11.3	9.7	6.4
Largest 5 Markets | Business segments
Segment Reporting Information [Line Items]
Capital Expenditures by Business Segment									59.3	83.4	103.5
Depreciation									93.2	106.0	107.7
Amortization of intangible assets									1.4	1.7	2.3
Global Markets | Business segments
Segment Reporting Information [Line Items]
Capital Expenditures by Business Segment									28.8	30.0	29.1
Depreciation									25.4	29.0	34.1
Amortization of intangible assets									1.8	2.3	2.6
Venezuela | Reconciling items
Segment Reporting Information [Line Items]
Capital Expenditures by Business Segment									4.3	5.4	9.0
Depreciation									$ 3.9	$ 9.5	$ 9.0