Restructuring - Restructuring Charges By Segment (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ 14.4	$ 5.0	$ 27.3	$ 5.4
Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	79.0		79.0
Restructuring Charges	14.4	5.0	27.3	5.4
Services Segment [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	42.4		42.4
Restructuring Charges	14.2	2.3	18.9	2.3
Software Segment [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	7.7		7.7
Restructuring Charges	0.5	0.2	(0.2)	0.5
Systems Segment [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	20.4		20.4
Restructuring Charges	0.9	0.8	3.5	0.9
Corporate, Non-Segment [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	8.5		8.5
Restructuring Charges	(1.2)	1.7	5.1	1.7
DN2020 Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	14.4		27.3
DN2020 Plan [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	70.1		70.1
DN2020 Plan [Member] | Services Segment [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	40.3		40.3
DN2020 Plan [Member] | Software Segment [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	5.8		5.8
DN2020 Plan [Member] | Systems Segment [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	16.8		16.8
DN2020 Plan [Member] | Corporate, Non-Segment [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	7.2		7.2
Multi-Year Transformation Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges		$ 5.0		$ 5.4
Delta Program [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	3.2		3.2
Delta Program [Member] | Services Segment [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	0.1		0.1
Delta Program [Member] | Software Segment [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	1.8		1.8
Delta Program [Member] | Systems Segment [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	0.0		0.0
Delta Program [Member] | Corporate, Non-Segment [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	1.3		1.3
Strategic Alliance Plan [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	5.7		5.7
Strategic Alliance Plan [Member] | Services Segment [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	2.0		2.0
Strategic Alliance Plan [Member] | Software Segment [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	0.1		0.1
Strategic Alliance Plan [Member] | Systems Segment [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	3.6		3.6
Strategic Alliance Plan [Member] | Corporate, Non-Segment [Member] | Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	$ 0.0		$ 0.0