Pension and Other Postretirement Plans (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Mar. 31, 2013	Dec. 31, 2007
Defined Benefit Pension Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Vesting percentage in accrued benefits from plan freeze						100.00%
Service cost	$ 48,000	$ 44,000	$ 142,000	$ 131,000
Interest cost	218,000	232,000	654,000	696,000
Expected return on plan assets	(284,000)	(268,000)	(850,000)	(803,000)
Amortization of prior service cost	1,000	1,000	3,000	3,000
Amortization of net loss	203,000	196,000	609,000	589,000
Net periodic benefit cost	186,000	205,000	558,000	616,000
Minimum required contribution	700,000		700,000
Company expected contributions to plans in fiscal year			400,000
Contributions payable, from prior plan years					100,000
Company contributions to plan			300,000
Chairman and President Non-Qualified Defined Benefit Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	44,000	42,000	133,000	126,000
Interest cost	201,000	228,000	601,000	684,000
Amortization of prior service cost	15,000	14,000	44,000	44,000
Amortization of net loss	293,000	286,000	880,000	857,000
Net periodic benefit cost	553,000	570,000	1,658,000	1,711,000
Company expected contributions to plans in fiscal year			2,000,000
Company contributions to plan			1,300,000
Aggregate average annual participant salary increase (as a percentage)			10.00%
Defined Benefit Postretirement Healthcare Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Interest cost	29,000	32,000	88,000	97,000
Amortization of prior service cost	26,000	25,000	77,000	77,000
Amortization of net loss	9,000	11,000	25,000	31,000
Net periodic benefit cost	$ 64,000	$ 68,000	$ 190,000	$ 205,000