Pension and Postretirement Benefit Plans (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Retired employees receiving health care and life insurance benefits	9
Post retirement benefits, age eligibility requirement	65 years
Post retirement benefits, service eligibility requirement	15 years
Unrecognized net actuarial gain	$ 38
Recognized transition obligation	2
Annual rate of increase in cost of covered health care benefits, next fiscal year	10.00%
Annual rate of increase in cost of covered health care benefits, two fiscal years	10.00%
Annual rate of increase in cost of covered health care benefits, three fiscal years	8.00%
Annual rate of increase in cost of covered health care benefits, four fiscal years	8.00%
Annual rate of increase in cost of covered health care benefits, five fiscal years and thereafter	6.00%
Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	(4)	(3)	(3)
Unrecognized net actuarial gain	(1)	9	(2)
Benefit obligation weighted average discount rate	3.50%	2.75%	3.50%
Effect of 1% rate increase on benefit obligation	6
Effect of 1% rate increase on net periodic benefit cost (less than one thousand)	1
Effect of 1% rate decrease on benefit obligation	(5)
Effect of 1% rate decrease on net periodic benefit cost (less than one thousand)	$ 1

Defined Benefit Plan Health Care Cost Trend Rate Assumed In Five Years And Thereafter

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- Definition

Defined Benefit Plan Health Care Cost Trend Rate Assumed In Four Years

+ References

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- Definition

Defined Benefit Plan Health Care Cost Trend Rate Assumed In Three Years

+ References

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- Definition

Defined Benefit Plan Health Care Cost Trend Rate Assumed In Two Years

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- Definition

Number Of Retired Employees Provided Health Care And Life Insurance

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- Definition

Postretirement Benefit Plan Recognized Transition Obligation Included In Other Comprehensive Income Net Periodic Benefit Cost

+ References

No definition available.

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- Definition

Post retirement benefits, age eligibility requirement

+ References

No definition available.

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- Definition

Post retirement benefits, service eligibility requirement.

+ References

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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

-Topic 715

-SubTopic 30

-Glossary Gain or Loss

-URI http://asc.fasb.org/extlink&oid=6514294

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=28361610&loc=d3e1928-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Gain or Loss

-URI http://asc.fasb.org/extlink&oid=6749293

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- Definition

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

+ References

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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.

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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.

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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

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (l)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

Reference 2: 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

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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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