Retirement Plans (Expected Benefit Payments) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Year one	$ 6,213	$ 5,142
Year two	6,545	5,590
Year three	6,992	6,113
Year four	7,579	6,649
Year five	8,265	7,252
Next five years	53,734	47,701
SERP [Member]
Defined Benefit Plan Disclosure [Line Items]
Year one	101	102
Year two	100	100
Year three	98	98
Year four	105	97
Year five	109	105
Next five years	616	597
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Year one	237	271
Year two	242	264
Year three	245	268
Year four	245	271
Year five	255	271
Next five years	$ 1,154	$ 1,343

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Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ 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 (f)

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

+ Details

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- Definition

Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

+ References

+ Details

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- Definition

Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

+ Details

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- Definition

Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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- Definition

Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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- Definition

Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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