Retirement Plans (Schedule Of Net Periodic Benefit Costs) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
United States Pension Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 23	$ 33	$ 31
Interest cost	771	707	748
Expected return on plan assets	(968)	(856)	(810)
Amortization of prior service cost	1	1	1
Recognized net actuarial loss	(65)	(212)	(194)
Net periodic benefit (income) cost	(108)	97	164
Net periodic benefit costs: Discount rate	4.00%	4.90%	4.00%
Net periodic benefit costs: Expected return on plan assets	5.50%	6.50%	6.50%
Projected benefit obligation	18,925	16,112	18,034
Fair value of plan assets	15,205	15,039	13,262
United Kingdom Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	360	348	338
Expected return on plan assets	(370)	(321)	(307)
Amortization of transition amount	(50)	(46)	(49)
Amortization of prior service cost	30	22	23
Recognized net actuarial loss	(185)	(229)	(221)
Net periodic benefit (income) cost	155	232	226
Projected benefit obligation: Discount rate	3.60%	4.60%	4.30%
Net periodic benefit costs: Expected return on plan assets	5.00%	5.80%	5.20%
Projected benefit obligation	8,797	8,450	8,034
Fair value of plan assets	6,757	6,769	6,051
United States Defined Benefit Plans with Benefit Obligations in Excess of Plan Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	18,925	12,513
Accumulated benefit obligation	18,925	12,513
Fair value of plan assets	15,205	11,321
United Kingdom Defined Benefit Plans with Benefit Obligations in Excess of Plan Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	8,797	8,450
Accumulated benefit obligation	8,797	8,450
Fair value of plan assets	$ 6,757	$ 6,769

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.

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The amount of the transition obligation or asset recognized in net periodic benefit cost.

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- Definition

The interest rate used to adjust for the time value of money for the plan.

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The interest rate used to adjust for the time value of money.

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Long-Term Rate of Return on Plan Assets

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(3)

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- Definition

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Projected Benefit Obligation

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Postretirement Benefit Obligation

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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.

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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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Expected Return on Plan Assets

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

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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.

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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.

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- Definition

If aggregate disclosures are presented, the aggregate pension accumulated benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 55

-Paragraph 17

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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.

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-Publisher FASB

-Name Accounting Standards Codification

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-Name Accounting Standards Codification

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

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