Defined benefit plan effect on pension expense.

No definition available.

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- Definition

Unrecognized Actuarial Gain (Loss) in Excess of Benefit Obligation, Percentage.

+ References

No definition available.

+ Details

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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.

+ References

+ Details

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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

+ Details

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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

+ Details

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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

+ Details

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- Definition

Amount of net gain (loss) recognized in net periodic benefit cost as a result of an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include, but are not limited to, lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contracts to cover vested benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 30
-Section 15
-Paragraph 6
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=7577095&loc=d3e8001-114927

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)(7)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- Definition

Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)(i)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920

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

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- Definition

Target allocation minimum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ 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 (d)(i)
-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 5
-Subparagraph (c)(i)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920

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- Definition

The ultimate trend rate for health care costs.

+ References

+ Details

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- Definition

Amount of employer's best estimate 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.

+ References

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Note G - Pensions and Other Postretirement Benefits (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements	$ 0	$ 3,800,000	$ 0
Unrecognized Actuarial Gain (Loss) in Excess of Benefit Obligation, Percentage	10.00%
Defined Benefit Plan, Effect of One Percentage Point Increase on Service and Interest Cost Components	$ 270,000
Defined Benefit Plan, Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation	2,000,000
Defined Benefit Plan, Effect of One Percentage Point Decrease on Service and Interest Cost Components	231,000
Defined Benefit Plan, Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation	$ 1,700,000
Equity Securities [Member]
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum	14.00%
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum	34.00%
Fixed Income Securities [Member]
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum	60.00%
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum	80.00%
Alternative Investments [Member]
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum	0.00%
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum	12.00%
Cash and Cash Equivalents [Member]
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum	0.00%
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum	10.00%
One Percentage Point Change in Assumed Rate of Return [Member]
Defined Benefit Plan Effect On Pension Expense	$ 692,000
One Percentage Point Increase in Discount Rate [Member]
Defined Benefit Plan Effect On Pension Expense	1,400,000
One Percentage Point Decrease in Discount Rate [Member]
Defined Benefit Plan Effect On Pension Expense	1,700,000
Pension Plan [Member]
Defined Contribution Plan, Employer Discretionary Contribution Amount	1,600,000	$ 1,600,000	$ 1,600,000
Pension Plan [Member] \| Minimum [Member]
Defined Benefit Plans, Estimated Future Employer Contributions in Next Fiscal Year	2,000,000
Pension Plan [Member] \| Maximum [Member]
Defined Benefit Plans, Estimated Future Employer Contributions in Next Fiscal Year	$ 6,000,000
Postretirement Health Coverage [Member] \| Retirees Age65 And Over [Member]
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate	0.00%
Postretirement Health Coverage [Member] \| Retirees Under Age65 [Member]
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate	5.00%