Consolidated Statements of Shareholders' Equity (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accumulated other comprehensive income (loss)
Tax effect on employee benefit funded status adjustment	$ (1,381)	$ (3,826)	$ (247)
Reinvested earnings
Cash dividends (in dollars per share)	$ 0.74	$ 0.6	$ 0.66
Capital in excess of par value
Issuance of treasury stock (in shares)	30	35	42

Aggregate dividends paid during the period for each share of common stock outstanding.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

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-Name Accounting Standards Codification

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+ References

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

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-Name Accounting Standards Codification

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-SubTopic 10

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

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+ References

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

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-Name Regulation S-X (SX)

-Number 210

-Section 04

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

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