Common Shareholders' Equity (Detail Textuals 1) (USD $)	0 Months Ended	1 Months Ended	12 Months Ended						12 Months Ended						3 Months Ended
	Jul. 02, 2012	Dec. 19, 2012	Dec. 31, 2012	Dec. 31, 2011	Nov. 19, 2012	May 14, 2012	Dec. 31, 2012 Other Postretirement Benefit Plans	Dec. 31, 2011 Other Postretirement Benefit Plans	Dec. 31, 2012 Treasury stock	Dec. 31, 2011 Treasury stock	Dec. 31, 2012 Stock Options	Dec. 31, 2011 Stock Options	Dec. 31, 2011 Stock Options Treasury stock	Dec. 31, 2012 Management Stock Options	Mar. 31, 2012 Option Holder Stock Options
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Number of options elected to exercise											80,000	78,000		71,000	9,000
Number of shares repurchased under exercise of options														2,500
Net shares issued out of treasury stock			72,000										72,000	68,500
Exercise of stock options			$ 445,000	$ 217,000					$ 555,000	$ 514,000				$ 215,000	$ 9,000
Tax benefit associated with option exercised			107,000										107,000	213,000	18,000
Cash dividend (in dollars per share)					$ 0.15	$ 0.15
Dividends, Cash	358,000	358,000		682,000
Estimated future annual expenses included in accumulated other comprehensive loss, net of deferred taxes							85,000	67,000
Other Comprehensive Loss, net of income tax benefit			44,000	39,000
Surrendered												112,000
Administrative charges of surrender transactions												5,170,000
Shares purchased during period			6,000										6,000
Tax benefit associated with surrender of shares												$ 176,000