Retirement Plans - Weighted Average Assumptions Used (Details)	Dec. 31, 2012	Dec. 31, 2011
Compensation and Retirement Disclosure [Abstract]
Discount rate	3.15%	2.80%
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation Average remaining service life at year end	13 years 1 month 6 days	12 years 9 months 18 days
Average rate of future compensation increase	2.00%	2.00%

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

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)(1)

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

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