Retirement Benefit Plans (Details) (USD $)	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jul. 02, 2011	Jun. 30, 2012	Jul. 02, 2011
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)	$ 47,272	$ 45,026	$ 96,729	$ 93,157
Pension Benefits [Member]
Significant disclosures relating to benefit plans [Abstract]
Service cost	674,549	530,251	1,347,196	1,060,503
Interest cost	713,980	737,419	1,427,960	1,474,837
Expected return on plan assets	(982,748)	(912,571)	(1,965,495)	(1,825,142)
Amortization of prior service cost	41,410	48,538	82,819	97,075
Amortization of the net loss	242,845	224,263	485,692	448,527
Net periodic benefit cost	690,036	627,900	1,378,172	1,255,800
Contributions required by the company in defined benefit plan in 2012	3,472,000		3,472,000
Contributions made by Company			1,881,000
Postretirement Benefits [Member]
Significant disclosures relating to benefit plans [Abstract]
Service cost	49,307	31,616	86,807	63,232
Interest cost	37,694	34,188	71,694	68,376
Expected return on plan assets	(24,270)	(24,825)	(48,520)	(49,650)
Amortization of prior service cost	(5,945)	(5,972)	(11,945)	(11,944)
Amortization of the net loss	0	0	0	0
Net periodic benefit cost	56,786	35,007	98,036	70,014
Contributions required by the company in defined benefit plan in 2012	155,000		155,000
Contributions made by Company			$ 62,000

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

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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

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-Topic 715

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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.

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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.

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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.

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

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

+ References

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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

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