Retirement Benefit Plans (Details) (USD $)	3 Months Ended
Mar. 30, 2013	Mar. 31, 2012
Significant disclosures relating to benefit plans [Abstract]
Percentage of voluntary contributions allowed to participants, maximum (in hundredths)	100.00%
Contributions made by the Company under Section 401(k)	$ 51,351	$ 49,456
Pension Benefits [Member]
Significant disclosures relating to benefit plans [Abstract]
Service cost	752,032	672,647
Interest cost	710,059	713,980
Expected return on plan assets	(1,100,912)	(982,747)
Amortization of prior service cost	61,356	41,409
Amortization of the net loss	355,859	242,847
Net periodic benefit cost	778,394	688,136
Contributions required by the company in defined benefit plan in 2013	1,121,000
Contributions made by Company	0
Postretirement Benefits [Member]
Significant disclosures relating to benefit plans [Abstract]
Service cost	50,642	37,500
Interest cost	35,522	34,000
Expected return on plan assets	(24,347)	(24,250)
Amortization of prior service cost	(5,972)	(6,000)
Amortization of the net loss	4,715	0
Net periodic benefit cost	60,560	41,250
Contributions required by the company in defined benefit plan in 2013	155,000
Contributions made by Company	$ 12,000

The amount of gains or losses recognized in net periodic benefit cost.

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The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

+ References

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- Definition

The increase in the fair value of plan assets from contributions made by the employer.

+ References

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The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan in the current remaining fiscal period. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

+ References

No definition available.

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- Definition

An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Return on Plan Assets

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- Definition

The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

+ References

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- Definition

The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ References

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- Definition

The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

+ References

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-Glossary Service Cost (Component of Net Periodic Pension Cost)

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

Maximum percentage of employee gross pay, by the terms of the plan, that the employer may contribute to a defined contribution plan.

+ References

No definition available.

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