Long-Term Debt (IKE Zone Act Senior Notes Due 2035) (Details) (USD $) In Thousands, unless otherwise specified				12 Months Ended		1 Months Ended
	Dec. 31, 2013	Dec. 31, 2013 Ike Zone Six Point Five Percent Tax Exempt Revenue Bonds Due Twenty Thirty Five [Member]	Dec. 31, 2012 Ike Zone Six Point Five Percent Tax Exempt Revenue Bonds Due Twenty Thirty Five [Member]	Dec. 31, 2013 Ike Zone Six Point Five Percent Tax Exempt Revenue Bonds Due Twenty Thirty Five [Member] Redeemed Prior To November 1, 2020 [Member]	Dec. 31, 2013 Ike Zone Six Point Five Percent Tax Exempt Revenue Bonds Due Twenty Thirty Five [Member] Redeemed On Or After November 1, 2020 [Member]	Dec. 31, 2010 Emergency Economic Stabilization Act Of 2008 [Member] Ike Zone Six Point Five Percent Tax Exempt Revenue Bonds Due Twenty Thirty Five [Member]	Dec. 02, 2010 Emergency Economic Stabilization Act Of 2008 [Member] Ike Zone Six Point Five Percent Tax Exempt Revenue Bonds Due Twenty Thirty Five [Member]
Debt Instrument [Line Items]
Senior notes, principal amount issued							$ 65,000
Stated interest rate	6.50%	6.50%	6.50%				6.50%
Maturity date						Nov. 01, 2035
Percentage of principal required if called				100.00%	100.00%
Minimum debt amount guaranteed by subsidiaries		$ 5,000