Employee Benefit Plans (Narrative) (Details) (USD $)	3 Months Ended	12 Months Ended
Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Narrative Description of Basis Used to Determine Overall Expected Long-term Rate-of-Return on Assets Assumption		the 25-year average return on pension portfolio assets was 8.04%, exceeding the expected long-term return of 7.75% utilized for 2014. Considering that future equity returns are partially a function of current starting valuations and the general level of interest rates is at a historically low point, one could start to build a case for lower expected returns going forward. However, such a case would be muted, especially in the case of equities, by the fact that global equity returns averaged 5.9% for the period from 2001 through 2014, versus close to a 10% average return for the previous seventy-five years. Additionally, according to a recent Vanguard Global Economics Team white paper, over half of the volatility in expected returns is not explained by current valuations. As potential returns remain widely dispersed and expected returns are based on a time horizon that will likely exceed the timing of current concerns, it is considered appropriate to maintain the forward expected long-term rate of return of 7.75%.
Defined Benefit Plan, Fair Value of Plan Assets	$ 38,967,000	$ 38,967,000	$ 34,848,000
Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Benefit Obligation	35,700,000	35,700,000	27,200,000
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	4.00%	4.00%	4.75%
Defined Benefit Plan, Benefit Obligation, Period Increase (Decrease)		4,100,000
Defined Benefit Plan, Actuarial Gain (Loss)		3,401,000	1,286,000
Defined Benefit Plan, Contributions by Employer	3,000,000	3,000,000	0
Defined Benefit Plan, Fair Value of Plan Assets	38,967,000	38,967,000	34,848,000	31,154,000
SERP [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Benefit Obligation	4,900,000	4,900,000	4,300,000
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	4.00%	4.00%	5.25%
Defined Benefit Plan, Actuarial Gain (Loss)		499,000	(167,000)
Defined Benefit Plan, Contributions by Employer		91,000	102,000
Defined Benefit Plan, Fair Value of Plan Assets	0	0	0	0
Impact Of Adoption Of Mortality Table [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Actuarial Gain (Loss)		$ 3,100,000

For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6503844

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (e)

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

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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

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-Section 50

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

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-Name Accounting Standards Codification

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

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Net increase or decrease in the plan benefit obligation during the reporting period.

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The increase in the fair value of plan assets from contributions made by the employer.

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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.

+ 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 (b)

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-Publisher FASB

-Name Accounting Standards Codification

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-Paragraph 50

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A narrative description of the basis used to determine the overall expected long-term rate-of-return on assets assumption, such as the general approach used, the extent to which the overall rate-of-return on assets assumption was based on historical returns, the extent to which adjustments were made to those historical returns to reflect expectations of future returns, and how those adjustments were determined. The description would generally consider the major categories of assets.

+ References

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-Publisher FASB

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