Retirement Benefits (Details Textual)	3 Months Ended
Mar. 31, 2013 Executive Participant	Mar. 31, 2012
Retirement Benefits (Textual) [Abstract]
Number of participants admitted in program	0
Number of executive officers participate in program	0
Discount rate used to determine net periodic pension cost	3.55%	4.48%

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

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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