Segment Information and Concentration of Risk - Segment Assets (Details) - USD ($) $ in Millions	Sep. 26, 2015	Dec. 31, 2014
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 2,226.7	$ 2,209.1
Operating Segments
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	2,116.0	2,082.4
Operating Segments \| AQH
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	585.8	585.7
Operating Segments \| SCS
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	370.1	339.6
Operating Segments \| ERG
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	421.6	365.0
Operating Segments \| RCH
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	533.1	549.6
Operating Segments \| CAS
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	155.3	179.3
Operating Segments \| AVC
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	50.1	63.2
Segment Reconciling Items
Segment Reporting, Asset Reconciling Item [Line Items]
Cash and cash equivalents, including current restricted cash	28.0	59.0
Deferred tax assets	43.7	28.1
Other assets, including long-term restricted investments	$ 39.0	$ 39.6

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Number 210

-Section 03

-Paragraph 12

-Article 7

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-SubTopic 10

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