Condensed Consolidated Statements of Income (Unaudited) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Revenues:
Transaction fees	$ 1,052.5	$ 1,083.2	$ 3,152.8	$ 3,138.2
Foreign exchange revenues	338.5	294.2	995.7	829.5
Other revenues	30.6	33.4	91.6	92.4
Total revenues	1,421.6	1,410.8	4,240.1	4,060.1
Expenses:
Cost of services	796.3	800.0	2,376.8	2,309.6
Selling, general and administrative	259.7	247.8	819.3	723.9
Total expenses	1,056.0	1,047.8	3,196.1	3,033.5
Operating income	365.6	363.0	1,044.0	1,026.6
Other income/(expense):
Interest income	1.4	1.1	4.1	3.6
Interest expense	(44.6)	(46.7)	(134.1)	(134.3)
Derivative gains/(losses), net	0.1	(5.3)	1.0	(4.7)
Other income, net	1.3	1.8	9.0	30.8
Total other expense, net	(41.8)	(49.1)	(120.0)	(104.6)
Income before income taxes	323.8	313.9	924.0	922.0
Provision for income taxes	54.3	74.2	136.0	208.9
Net income	$ 269.5	$ 239.7	$ 788.0	$ 713.1
Earnings per share:
Basic (in dollars per share)	$ 0.45	$ 0.38	$ 1.29	$ 1.12
Diluted (in dollars per share)	$ 0.45	$ 0.38	$ 1.29	$ 1.12
Weighted-average shares outstanding:
Basic (in shares)	601.5	624.9	610.5	634.3
Diluted (in shares)	604.2	627.1	613.1	638.3
Cash dividends declared per common share	$ 0.10	$ 0.08	$ 0.3	$ 0.23