Retirement Agreements And Other Postretirement Benefits (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Service cost - benefits earned during the year	$ 0	$ 2,545	$ 0	$ 5,090
Interest cost on the projected benefit obligation	9,217	8,781	18,434	17,562
Amortization of unrecognized losses	2,153	2,235	4,306	4,470
Net periodic benefits costs	11,370	$ 13,561	22,740	$ 27,122
Employee benefits and other payments	$ 9,514,000		$ 9,514,000		$ 8,487,000

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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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

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