Benefit Plans (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012 noncontributory_defined_benefit_pension_plans	Jan. 01, 2012	Jan. 02, 2011
Benefit Plans (Textual) [Abstract]
Deferred Compensation Arrangement with Individual, Recorded Liability	$ 6.6
Additional Benefit Plans (Textual) [Abstract]
Number of Non-Contributory Defined Benefit Pension Plans	2
Period of average compensation for pension benefit computation	5 years
Age limit for a lump sum payment	55
Long-term portion of the pension liability	19.5	16.7
Recognized as net periodic benefit cost	0.3
Retirement age	65
Expense related to contributions	0.4	0.3	0.2
Total deferred compensation liability	7.8	8.0
Deferred Compensation Liability, Current	1.1	0.6
Former Chief Operating Officer [Member]
Benefit Plans (Textual) [Abstract]
Discounted retirement benefits under non-qualified deferred compensation agreement, including taxes as specified in the deferred compensation agreement		4.4
Non-qualified deferred compensation arrangement with individual taxes as specified in agreement		2
Recognized settlement charges		$ 0

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- Definition

Deferred compensation arrangement with individual taxes as specified in agreement.

+ References

No definition available.

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- Definition

Period used to average compensation for calculation of pension plan benefits.

+ References

No definition available.

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- Definition

Defined benefit plan settlement charges.

+ References

No definition available.

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- Definition

Minimum age to be eligible to receive lump sum payment upon benefit.

+ References

No definition available.

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- Definition

Number of Non-Contributory Defined Benefit Pension Plans

+ References

No definition available.

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- Definition

Retirement age.

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No definition available.

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- Definition

The amount of distributions made to the individual during the period.

+ References

No definition available.

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- Definition

The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64, 65

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable within one year (or the operating cycle, if longer). Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

+ References

No definition available.

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- Definition

This represents the noncurrent liability recognized in the balance sheet that is associated with the defined benefit pension plans.

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

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- Definition

Before tax amount of the income statement impact of the reclassification adjustment for actuarial gain (loss) recognized as a component of net periodic benefit cost.

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