Restructuring Plans (Schedule of Restructuring Reserve by Segment) (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) business_line	Sep. 30, 2014 USD ($)
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	$ 5.6	$ 1.9	$ 19.0	$ 12.4
Cumulative	67.4		67.4
Expected Total	70.8		70.8
Employee Termination Costs
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	4.8		13.3
Cumulative	49.9		49.9
Expected Total	53.2		53.2
Property Costs
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	0.1		1.9
Cumulative	5.9		5.9
Expected Total	5.9		5.9
Other
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	0.7		3.8
Cumulative	11.6		11.6
Expected Total	11.7		$ 11.7
Gaming
Restructuring Cost and Reserve [Line Items]
Number of immaterial business lines with exit costs | business_line			2
Business Segment
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	3.7	1.9	$ 11.8	10.5
Business Segment | Gaming
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	3.2		10.1
Cumulative	32.2		32.2
Expected Total	35.5		35.5
Business Segment | Gaming | Employee Termination Costs
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	2.6		9.4
Cumulative	27.7		27.7
Expected Total	31.0		31.0
Business Segment | Gaming | Property Costs
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	0.0		0.0
Cumulative	0.9		0.9
Expected Total	0.9		0.9
Business Segment | Gaming | Other
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	0.6		0.7
Cumulative	3.6		3.6
Expected Total	3.6		3.6
Business Segment | Lottery
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	0.0	$ 0.4	0.2	$ 1.6
Cumulative	3.7		3.7
Expected Total	3.7		3.7
Business Segment | Lottery | Employee Termination Costs
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	0.0		0.2
Cumulative	3.3		3.3
Expected Total	3.3		3.3
Business Segment | Lottery | Property Costs
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	0.0		0.0
Cumulative	0.4		0.4
Expected Total	0.4		0.4
Business Segment | Lottery | Other
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	0.0		0.0
Cumulative	0.0		0.0
Expected Total	0.0		0.0
Business Segment | Interactive
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	0.5		1.5
Cumulative	10.6		10.6
Expected Total	10.6		10.6
Business Segment | Interactive | Employee Termination Costs
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	0.4		1.3
Cumulative	5.1		5.1
Expected Total	5.1		5.1
Business Segment | Interactive | Property Costs
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	0.0		0.0
Cumulative	0.4		0.4
Expected Total	0.4		0.4
Business Segment | Interactive | Other
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	0.1		0.2
Cumulative	5.1		5.1
Expected Total	5.1		5.1
Unallocated corporate
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	1.9		7.2
Cumulative	20.9		20.9
Expected Total	21.0		21.0
Unallocated corporate | Employee Termination Costs
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	1.8		2.4
Cumulative	13.8		13.8
Expected Total	13.8		13.8
Unallocated corporate | Property Costs
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	0.1		1.9
Cumulative	4.2		4.2
Expected Total	4.2		4.2
Unallocated corporate | Other
Restructuring Cost and Reserve [Line Items]
Employee termination and restructuring	0.0		2.9
Cumulative	2.9		2.9
Expected Total	$ 3.0		$ 3.0