Condensed Consolidating Financial Statements - Statement of Operations and Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 27, 2016	Mar. 29, 2015
Condensed Financial Statements, Captions [Line Items]
Service revenues	$ 82.6	$ 87.3
Product sales	70.4	69.8
Total revenues	153.0	157.1
Cost of service revenues	60.3	66.0
Cost of product sales	56.8	52.8
Total costs	117.1	118.8
Gross profit	35.9	38.3
Selling, general and administrative expenses	43.2	38.3
Research and development expenses	2.9	3.9
Operating loss from continuing operations	(10.2)	(3.9)
Other income (expense):
Interest income (expense), net	(8.7)	(8.8)
Other income (expense), net	0.3	0.1
Total other expense, net	(8.4)	(8.7)
Loss from continuing operations before income taxes	(18.6)	(12.6)
Provision (benefit) for income taxes from continuing operations	3.6	1.9
Loss from continuing operations	(22.2)	(14.5)
Income (loss) from discontinued operations	0.0	(1.7)
Equity in net income (loss) of subsidiaries	0.0	0.0
Net loss	(22.2)	(16.2)
Comprehensive income (loss)	(22.2)	(16.4)
Parent Company
Condensed Financial Statements, Captions [Line Items]
Service revenues	0.0	0.0
Product sales	0.0	0.0
Total revenues	0.0	0.0
Cost of service revenues	0.0	0.0
Cost of product sales	0.0	0.0
Total costs	0.0	0.0
Gross profit	0.0	0.0
Selling, general and administrative expenses	1.3	5.1
Research and development expenses	0.0	0.0
Operating loss from continuing operations	(1.3)	(5.1)
Other income (expense):
Interest income (expense), net	(8.6)	(8.7)
Other income (expense), net	0.0	0.0
Total other expense, net	(8.6)	(8.7)
Loss from continuing operations before income taxes	(9.9)	(13.8)
Provision (benefit) for income taxes from continuing operations	0.1	0.2
Loss from continuing operations	(10.0)	(14.0)
Income (loss) from discontinued operations		(3.3)
Equity in net income (loss) of subsidiaries	(12.2)	1.1
Net loss	(22.2)	(16.2)
Comprehensive income (loss)	(22.2)	(16.4)
Subsidiary Guarantors on a Combined Basis
Condensed Financial Statements, Captions [Line Items]
Service revenues	77.4	85.5
Product sales	59.0	61.9
Total revenues	136.4	147.4
Cost of service revenues	56.7	64.7
Cost of product sales	48.0	47.3
Total costs	104.7	112.0
Gross profit	31.7	35.4
Selling, general and administrative expenses	39.6	31.0
Research and development expenses	2.9	3.8
Operating loss from continuing operations	(10.8)	0.6
Other income (expense):
Interest income (expense), net	(0.1)	(0.1)
Other income (expense), net	0.0	(3.0)
Total other expense, net	(0.1)	(3.1)
Loss from continuing operations before income taxes	(10.9)	(2.5)
Provision (benefit) for income taxes from continuing operations	3.2	1.8
Loss from continuing operations	(14.1)	(4.3)
Income (loss) from discontinued operations		0.8
Equity in net income (loss) of subsidiaries	1.9	4.6
Net loss	(12.2)	1.1
Comprehensive income (loss)	(12.2)	1.1
Non-Guarantors on a Combined Basis
Condensed Financial Statements, Captions [Line Items]
Service revenues	5.2	1.8
Product sales	13.1	10.8
Total revenues	18.3	12.6
Cost of service revenues	3.6	1.3
Cost of product sales	10.5	8.4
Total costs	14.1	9.7
Gross profit	4.2	2.9
Selling, general and administrative expenses	2.3	2.2
Research and development expenses	0.0	0.1
Operating loss from continuing operations	1.9	0.6
Other income (expense):
Interest income (expense), net	0.0	0.0
Other income (expense), net	0.3	3.1
Total other expense, net	0.3	3.1
Loss from continuing operations before income taxes	2.2	3.7
Provision (benefit) for income taxes from continuing operations	0.3	(0.1)
Loss from continuing operations	1.9	3.8
Income (loss) from discontinued operations		0.8
Equity in net income (loss) of subsidiaries	0.0	0.0
Net loss	1.9	4.6
Comprehensive income (loss)	1.9	4.4
Eliminations
Condensed Financial Statements, Captions [Line Items]
Service revenues	0.0	0.0
Product sales	(1.7)	(2.9)
Total revenues	(1.7)	(2.9)
Cost of service revenues	0.0	0.0
Cost of product sales	(1.7)	(2.9)
Total costs	(1.7)	(2.9)
Gross profit	0.0	0.0
Selling, general and administrative expenses	0.0	0.0
Research and development expenses	0.0	0.0
Operating loss from continuing operations	0.0	0.0
Other income (expense):
Interest income (expense), net	0.0	0.0
Other income (expense), net	0.0	0.0
Total other expense, net	0.0	0.0
Loss from continuing operations before income taxes	0.0	0.0
Provision (benefit) for income taxes from continuing operations	0.0	0.0
Loss from continuing operations	0.0	0.0
Income (loss) from discontinued operations		0.0
Equity in net income (loss) of subsidiaries	10.3	(5.7)
Net loss	10.3	(5.7)
Comprehensive income (loss)	$ 10.3	$ (5.5)