Income Taxes - Narrative (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 29, 2014	Jun. 30, 2013	Dec. 29, 2013
Income Tax Disclosure [Abstract]
Federal annual utilization of NOL carryforwards limit, next five years	$ 27
Threshold period for change in allowed annual amount of NOL to be recognized	5 years
Federal annual utilization of NOL carryforwards limit, after year five	11.6
Unrecognized tax benefits that if recognized would affect effective tax rate			15.8
Unrecognized tax benefits increase related to the CEI acquisition	3.0
Income tax penalties and interest expense	0.1
Benefit for income tax penalties and interest related to reversal of prior positions		$ 0.2

Operating Loss Carryforwards, Federal Annual Utilization Limit, After Year Five

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- Definition

Operating Loss Carryforwards, Federal Annual Utilization Limit, Five Years Succeeding Initial Ownership Change

+ References

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- Definition

Threshold Period for Change in Allowed Annual Amount of Operating Loss Carryforward to be Recognized

+ References

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- Definition

Unrecognized Tax Benefits, Income Tax Penalties and Interest Benefit, Reversals of Prior Positions

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- Definition

Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)

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Amount of increase in unrecognized tax benefits resulting from acquisitions.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (b)

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