Pension And Postretirement Benefit Costs (Narrative) (Details) (USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Defined Contribution Plan Disclosure [Line Items]
Defined Contribution Plan, Employer Matching Contribution, Percent	6.00%	6.00%	6.00%
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 69,083	$ 64,533	$ 61,361
Defined contribution plan, employer matching percentage of percentage of employee contribution	25.00%	25.00%	25.00%
Defined contribution, expected employer contribution in the next fiscal year	70,000
Defined contribution, maximum match	2,500
Pension Benefits [Member]
Defined Contribution Plan Disclosure [Line Items]
Expected contribution by the employer	2,470,000
Percentage allowance fluctuation before assets	5.00%
Postretirement Benefits [Member]
Defined Contribution Plan Disclosure [Line Items]
Expected contribution by the employer	1,630,000
Current portion of accrued benefit cost	$ 1,630,000	$ 1,600,000

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Defined contribution plan, employer matching percentage of percentage of employee contribution

+ References

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- Definition

Defined contribution plan, expected employer contribution in the next fiscal year

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- Definition

Fluctuation Before Assets Rebalanced Percentage

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- Definition

The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. 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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

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- Definition

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

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Maximum amount per employee, by the terms of the plan, that the employer may contribute to a defined contribution plan.

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- Definition

For a classified balance sheet, the amount recognized in balance sheet as a current liability associated with an underfunded defined benefit plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 45

-Paragraph 2

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Current Liabilities

-URI http://asc.fasb.org/extlink&oid=6509677

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-Publisher FASB

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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