Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Line Items]
Goodwill	$ 1,271.3	$ 1,234.9	$ 1,269.1
Accumulated impairment losses	(470.9)	(470.9)	(470.9)
Beginning balance	764.0	798.2
Divestitures	(10.0)	(16.0)
Transferred to assets held for sale	(1.4)
Currency translation adjustment	47.8	(18.2)
Ending balance	800.4	764.0
Eurasia Banking Segment [Member]
Goodwill [Line Items]
Goodwill	590.4	579.2	598.6
Accumulated impairment losses	(291.7)	(291.7)	(291.7)
Beginning balance	287.5	306.9
Divestitures	(6.4)	(12.1)
Transferred to assets held for sale	(1.4)
Currency translation adjustment	19.0	(7.3)
Ending balance	298.7	287.5
Americas Banking Segment [Member]
Goodwill [Line Items]
Goodwill	444.7	431.3	437.3
Accumulated impairment losses	(122.0)	(122.0)	(122.0)
Beginning balance	309.3	315.3
Divestitures	(2.4)	0.0
Transferred to assets held for sale	0.0
Currency translation adjustment	15.8	(6.0)
Ending balance	322.7	309.3
Retail Segment [Member]
Goodwill [Line Items]
Goodwill	236.2	224.4	233.2
Accumulated impairment losses	(57.2)	(57.2)	$ (57.2)
Beginning balance	167.2	176.0
Divestitures	(1.2)	(3.9)
Transferred to assets held for sale	0.0
Currency translation adjustment	13.0	(4.9)
Ending balance	$ 179.0	$ 167.2

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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