Benefit Plans (Schedule of Assumptions Used) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Defined Benefit Plan Disclosure [Line Items]
Assumptions used to determine benefit obligations as of measurement date: Discount rate	3.89%	4.18%	5.28%
Assumptions used to determine benefit obligations as of measurement date: Rate of compensation increase	4.00%	4.00%	4.00%
Assumptions used to determine net periodic benefit cost: Discount rate	4.18%	5.28%	5.79%
Assumptions used to determine net periodic benefit cost: Expected long-term return on plan assets	7.00%	7.50%	8.00%
Assumptions used to determine net periodic benefit cost: Rate of compensation increase	4.00%	4.50%	4.50%
Asset allocations as of measurement date:	100.00%	100.00%	100.00%
Common Stock, Value, Issued	$ 4,503	$ 4,419
Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocations as of measurement date:	35.00%	3.00%	12.00%
Equity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocations as of measurement date:	22.00%	25.00%	18.00%
Corporate debt securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocations as of measurement date:	3.00%	7.00%	7.00%
Municipal securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocations as of measurement date:	38.00%	62.00%	59.00%
Insurance contracts [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocations as of measurement date:	2.00%	3.00%	4.00%
Corporation [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocations as of measurement date:	0.20%	0.30%	0.60%
Common Stock, Value, Issued	$ 40	$ 36	52

Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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- Definition

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

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph j

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(1)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

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- Definition

Expected rate of compensation increases (for pay-related plans).

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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 20

-Section 50

-Paragraph 1

-Subparagraph (k)(3)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 87

-Paragraph 264

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph j

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: 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

-URI http://asc.fasb.org/extlink&oid=6512013

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- Definition

Expected rate of compensation increases (for pay-related plans).

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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