Defined Benefit Plan, Net Periodic Benefit Cost, Annual Change Due to Plan Ammendment

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- Definition

Defined Benefit Plan, Plan Ammendment, Amortization Period

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- Definition

Number of 401k Plans

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- Definition

Amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover, salary, and temporary deviation from the substantive plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Gain or Loss
-URI http://asc.fasb.org/extlink&oid=49168827

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- References

No definition available.

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- References

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- Definition

Disclosure under FAS 132R, before it was amended by FAS 158, of the portion of prior service costs and credits, due to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation, which has not yet been recognized as components of net periodic benefit cost.

+ 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 (j)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Prior Service Cost
-URI http://asc.fasb.org/extlink&oid=49177896

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- References

No definition available.

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- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

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- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ References

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

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- Definition

Amount included in accumulated other comprehensive income (AOCI) related to gain (loss) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position.

+ References

No definition available.

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- Definition

Amount included in accumulated other comprehensive income (AOCI) related to prior service cost (credit) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position.

+ References

No definition available.

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- Definition

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Health Care Cost Trend Rate
-URI http://asc.fasb.org/extlink&oid=6514820

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (l)
-URI http://asc.fasb.org/extlink&oid=65897934&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

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)(2)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- Definition

The ultimate trend rate for health care costs.

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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 (decrease) during the reporting period in the amount due to fund pension and non-pension benefits to employees, retired and disabled former employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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Post Retirement Benefits (Details)	12 Months Ended
Post Retirement Benefits (Details)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($) Plan	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2010 USD ($)
Postretirement benefits:
Number of 401k plans \| Plan		3
Amounts that will be amortized from accumulated other comprehensive income in next fiscal year:
Interest cost		$ 323,000	$ 316,000	$ 277,000
Postretirement benefits
Postretirement benefits:
Decrease in post retirement obligations					$ 10,282,000
Amortization period					20 years
Change in net periodic benefit cost due to plan amendment		496,000	496,000	$ 496,000
Defined Benefit Plan, Actuarial Gain (Loss)		320,000	(48,000)
Prior service credit not yet recognized		3,634,000	3,655,000
Amounts that will be amortized from accumulated other comprehensive income in next fiscal year:
Interest cost		$ 323,000	$ 316,000
Assumed health care cost trend rates:
Health care cost trend rate assumed for next fiscal year		7.00%	6.00%
Ultimate health care cost trend rate		5.00%	5.00%
Effect of changing the health care cost trend rate by one-percentage point for each future year:
Effect on total of service and interest cost components, 1 - percentage point increase		$ 43,000
Effect on total of service and interest cost components, 1 - percentage point decrease		(50,000)
Effect on post retirement benefit obligation, 1 - percentage point increase		941,000
Effect on post retirement benefit obligation, 1 - percentage point decrease		$ (800,000)
Forecast \| Postretirement benefits
Postretirement benefits:
Change in net periodic benefit cost due to plan amendment	$ 496,000
Defined Benefit Plan, Actuarial Gain (Loss)	49,000
Amounts that will be amortized from accumulated other comprehensive income in next fiscal year:
Amortization of prior service credit, net of tax	(496,000)
Amortization of loss, net of tax	(149,000)
Interest cost	$ 298,000