Segment information - Revenue And Operating Profits (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Segment Reporting Information [Line Items]
Revenues	$ 721.8	$ 776.1
Operating Profit (Loss)	13.8	12.9
Total reportable segments
Segment Reporting Information [Line Items]
Revenues	688.9	755.6
Operating Profit (Loss)	44.2	59.8
Corporate expenses
Segment Reporting Information [Line Items]
General, administrative and other expenses	(17.6)	(17.6)
Foreign currency transaction losses	1.3	(4.8)
Reconciliation of segment policies to GAAP	3.2	3.2
Other items not allocated to segments
Segment Reporting Information [Line Items]
Acquisitions and dispositions, Revenues	0.8	0.0
Reorganization and Restructuring	(6.0)	(1.5)
U.S. retirement plans	(7.3)	(8.3)
Acquisitions and dispositions	(5.8)	0.0
Largest 5 Markets | Total reportable segments
Segment Reporting Information [Line Items]
Revenues	454.4	487.6
Operating Profit (Loss)	13.4	28.1
Global Markets | Total reportable segments
Segment Reporting Information [Line Items]
Revenues	213.6	245.2
Operating Profit (Loss)	30.8	31.2
Venezuela
Segment Reporting Information [Line Items]
Foreign currency transaction losses		(18.0)
Venezuela | Other items not allocated to segments
Segment Reporting Information [Line Items]
Revenues	32.1	20.5
Operating Profit (Loss)	1.8	(17.9)
U.S. | Total reportable segments
Segment Reporting Information [Line Items]
Revenues	178.8	183.6
Operating Profit (Loss)	(2.2)	8.3
France | Total reportable segments
Segment Reporting Information [Line Items]
Revenues	104.8	105.7
Operating Profit (Loss)	4.5	4.1
Mexico | Total reportable segments
Segment Reporting Information [Line Items]
Revenues	74.9	85.7
Operating Profit (Loss)	3.2	7.9
Brazil | Total reportable segments
Segment Reporting Information [Line Items]
Revenues	60.0	73.8
Operating Profit (Loss)	6.1	6.1
Canada | Total reportable segments
Segment Reporting Information [Line Items]
Revenues	35.9	38.8
Operating Profit (Loss)	1.8	1.7
Latin America | Total reportable segments
Segment Reporting Information [Line Items]
Revenues	79.2	90.8
Operating Profit (Loss)	17.5	16.5
EMEA | Total reportable segments
Segment Reporting Information [Line Items]
Revenues	95.4	115.7
Operating Profit (Loss)	6.9	8.2
Asia | Total reportable segments
Segment Reporting Information [Line Items]
Revenues	39.0	38.7
Operating Profit (Loss)	6.4	6.5
Payment Services | Total reportable segments
Segment Reporting Information [Line Items]
Revenues	20.9	22.8
Operating Profit (Loss)	$ 0.0	$ 0.5