Long-Term Debt (Long-Term Debt) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014		Dec. 31, 2013
Debt Instrument [Line Items]
Long-term debt, beginning balance	$ 8,129,546
Payments and Retirements	(14,479)
New Borrowings	10,706
Long-term debt, ending balance	8,125,773
Less: Debt (Discount)/Premium	2,524		2,037
Less: Current Portion	(365,625)		(257,916)
Principal Outstanding	7,762,672		7,873,667
Weighted average interest rate	7.94%	[1]
Senior Unsecured Debt [Member]
Debt Instrument [Line Items]
Long-term debt, beginning balance	8,107,066
Payments and Retirements	(14,375)
Long-term debt, ending balance	8,092,691
Weighted average interest rate	7.95%	[1]
Other Secured Debt [Member]
Debt Instrument [Line Items]
Long-term debt, beginning balance	13,550
Payments and Retirements
New Borrowings	10,706
Long-term debt, ending balance	24,256
Weighted average interest rate	3.54%	[1]
Rural Utilities Service Loan Contracts [Member]
Debt Instrument [Line Items]
Long-term debt, beginning balance	8,930
Payments and Retirements	(104)
Long-term debt, ending balance	$ 8,826
Weighted average interest rate	6.15%	[1]

[1] Interest rate includes amortization of debt issuance costs and debt premiums or discounts. The interest rates at March 31, 2014 represent a weighted average of multiple issuances.