Accumulated Other Comprehensive Income (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ 4,798,000	$ 3,148,000	$ 4,872,000	$ 3,187,000
Other comprehensive income before reclassifications	0	0
Amounts reclassified from accumulated other comprehensive income, before tax	(107,000)	(53,000)
Other Comprehensive Income (Loss), Tax	33,000	14,000
Derivative [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(27,000)	(40,000)	(30,000)	(54,000)
Other comprehensive income before reclassifications	0	0
Derivative Instruments, Loss Reclassified from Accumulated OCI into Income, Effective Portion	5,000	21,000
Other Comprehensive Income (Loss), Tax	(2,000)	(7,000)
Other Postretirement Benefit Plans, Defined Benefit [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax	4,825,000	3,188,000	4,902,000	3,241,000
Other comprehensive income before reclassifications	0	0
Other Comprehensive Income (Loss), Reclassification, Pension and Other Postretirement Benefit Plans, Net Gain (Loss) Recognized in Net Periodic Benefit Cost, before Tax	(112,000)	(74,000)
Other Comprehensive Income (Loss), Tax	$ 35,000	$ 21,000