Retirement Benefit Plans (Details) (USD $)	3 Months Ended	6 Months Ended
Jun. 28, 2014	Jun. 29, 2013	Jun. 28, 2014	Jun. 29, 2013
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)	$ 50,964	$ 49,385	$ 103,455	$ 100,736
Pension Benefits [Member]
Significant disclosures relating to benefit plans [Abstract]
Service cost	698,424	752,030	1,396,848	1,504,062
Interest cost	829,258	710,058	1,658,557	1,420,117
Expected return on plan assets	(1,202,630)	(1,100,912)	(2,405,262)	(2,201,824)
Amortization of prior service cost	54,646	61,359	109,293	122,715
Amortization of the net loss	236,032	355,857	472,065	711,716
Net periodic benefit cost	615,730	778,392	1,231,501	1,556,786
Contributions required by the Company in defined benefit plan in 2014			2,500,000
Contributions made by Company			635,000
Postretirement Benefits [Member]
Significant disclosures relating to benefit plans [Abstract]
Service cost	44,951	50,642	86,951	101,284
Interest cost	38,491	35,521	78,741	71,043
Expected return on plan assets	(25,156)	(24,347)	(47,406)	(48,694)
Amortization of prior service cost	(5,945)	(5,972)	(11,945)	(11,944)
Amortization of the net loss	0	4,715	0	9,430
Net periodic benefit cost	52,341	60,559	106,341	121,119
Contributions required by the Company in defined benefit plan in 2014			63,000
Contributions made by Company			$ 13,000

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

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- Definition

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

+ Details

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- Definition

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

+ References

+ Details

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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

-URI http://asc.fasb.org/extlink&oid=6512136

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Expected Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512171

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)(3)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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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

+ Details

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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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)(1)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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

-URI http://asc.fasb.org/extlink&oid=6525008

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan in the current remaining fiscal period.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

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