Long-Term Debt (Details) (USD $)	12 Months Ended									12 Months Ended					12 Months Ended				12 Months Ended							12 Months Ended																																																		12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011 Pension Plan Noncash Contribution [Member]	Dec. 31, 2012 Unsecured Letter of Credit Facility [Member]	Dec. 31, 2011 Unsecured Letter of Credit Facility [Member]	Dec. 31, 2012 Unsecured Letter of Credit Facility [Member] March 2013 [Member]	Dec. 31, 2012 Unsecured Letter of Credit Facility [Member] September 2013 [Member]	Dec. 31, 2012 Revolving Credit Facility [Member]	Dec. 31, 2012 Senior Note Due 1/15/2013 [Member]	May 31, 2012 Senior Note Due 5/1/2014 [Member]	Sep. 30, 2012 Senior Note Due 4/15/2015 [Member]	Jun. 18, 2012 Senior Note Due 4/15/2015 [Member]	Sep. 30, 2012 Senior Note Due 4/15/2017 [Member]	Dec. 31, 2012 Senior Note Due 7/1/2021 [Member]	Dec. 31, 2012 Senior Note Due 10/14/2016 [Member]	Dec. 31, 2012 CoBank Term Loan 2012 [Member]	Dec. 31, 2012 CoBank Term Loan 2013 [Member]	Dec. 31, 2012 Senior Note Due 2023 Issued 10/1/2012 [Member]	Dec. 31, 2012 Senior Note Due 2023 Issued 8/15/2012 [Member]	Dec. 31, 2012 April 2015 and 2017 Notes [Member]	May 17, 2012 The Notes [Member]	Dec. 31, 2012 Senior Note [Member]	Dec. 31, 2011 Senior Note [Member]	Dec. 31, 2011 Rural Utilities Service [Member]	Dec. 31, 2012 Rural Utilities Service [Member] Loan Contracts [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Senior Note Due 1/15/2013 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Senior Note Due 1/15/2013 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Senior Note Due 5/1/2014 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Senior Note Due 5/1/2014 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Senior Note Due 3/15/2015 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Senior Note Due 3/15/2015 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Senior Note Due 4/15/2015 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Senior Note Due 4/15/2015 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Senior Note Due 4/15/2017 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Senior Note Due 4/15/2017 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Senior Note Due 10/1/2018 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Senior Note Due 10/1/2018 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Senior Note Due 1/15/2023 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Senior Note Due 1/15/2023 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Senior Note Due 3/15/2019 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Senior Note Due 3/15/2019 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Senior Note Due 4/15/2020 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Senior Note Due 4/15/2020 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Senior Note Due 7/1/2021 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Senior Note Due 7/1/2021 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Senior Note Due 4/15/2022 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Senior Note Due 4/15/2022 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Senior Note Due 1/15/2027 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Senior Note Due 1/15/2027 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Senior Note Due 2/15/2028 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Senior Note Due 2/15/2028 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Senior Note Due 10/15/2029 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Senior Note Due 10/15/2029 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Senior Note Due 8/15/2031 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Senior Note Due 8/15/2031 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Debenture Due 11/1/2025 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Debenture Due 11/1/2025 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Debenture Due 8/15/2026 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Debenture Due 8/15/2026 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Debenture Due 10/1/2034 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Debenture Due 10/1/2034 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Debenture Due 7/1/2035 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Debenture Due 7/1/2035 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Debenture Due 10/1/2046 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Debenture Due 10/1/2046 [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Senior Note Due 10/14/2016 [Member]		Dec. 31, 2011 Senior Unsecured Debt [Member] Senior Note Due 10/14/2016 [Member]		Dec. 31, 2012 Senior Unsecured Debt [Member] Debentures [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Debentures [Member]	Dec. 31, 2012 Senior Unsecured Debt [Member] Subsidiary Senior Notes Due 12/1/2012 [Member]	Dec. 31, 2011 Senior Unsecured Debt [Member] Subsidiary Senior Notes Due 12/1/2012 [Member]	Dec. 31, 2012 Industrial Development Revenue Bonds [Member]
Debt Instrument [Line Items]
Long-term debt, beginning balance	$ 8,349,521,000																$ 143,000,000	$ 130,000,000					$ 8,669,696,000	$ 8,039,774,000	$ 200,000,000	$ 10,197,000	$ 8,325,774,000	$ 502,658,000	$ 580,724,000	$ 200,000,000	$ 600,000,000	$ 300,000,000	$ 300,000,000	$ 374,803,000	$ 500,000,000	$ 1,040,685,000	$ 1,100,000,000	$ 600,000,000	$ 600,000,000	$ 850,000,000	$ 0	$ 434,000,000	$ 434,000,000	$ 1,100,000,000	$ 1,100,000,000	$ 500,000,000	$ 0	$ 500,000,000	$ 500,000,000	$ 345,858,000	$ 345,858,000	$ 200,000,000	$ 200,000,000	$ 50,000,000	$ 50,000,000	$ 945,325,000	$ 945,325,000	$ 138,000,000	$ 138,000,000	$ 1,739,000	$ 1,739,000	$ 628,000	$ 628,000	$ 125,000,000	$ 125,000,000	$ 193,500,000	$ 193,500,000	$ 517,500,000	[1]	$ 575,000,000	[1]	$ 8,919,696,000	$ 8,325,774,000	$ 0	$ 36,000,000	$ 13,550,000
Payments	(756,953,000)																									(875,000)	(756,078,000)																																																	0
Borrowings	1,350,000,000																									0	1,350,000,000																																																	0
Less: Debt Discount	(71,000)	(31,113,000)
Less: Current Portion	(560,550,000)	(94,016,000)
Principal Outstanding	8,381,947,000	8,224,392,000
Long-term debt, ending balance	8,942,568,000	8,349,521,000															143,000,000	130,000,000					8,669,696,000	8,039,774,000	200,000,000	9,322,000	8,919,696,000	502,658,000	580,724,000	200,000,000	600,000,000	300,000,000	300,000,000	374,803,000	500,000,000	1,040,685,000	1,100,000,000	600,000,000	600,000,000	850,000,000	0	434,000,000	434,000,000	1,100,000,000	1,100,000,000	500,000,000	0	500,000,000	500,000,000	345,858,000	345,858,000	200,000,000	200,000,000	50,000,000	50,000,000	945,325,000	945,325,000	138,000,000	138,000,000	1,739,000	1,739,000	628,000	628,000	125,000,000	125,000,000	193,500,000	193,500,000	517,500,000	[1]	575,000,000	[1]	8,919,696,000	8,325,774,000	0	36,000,000	13,550,000
Interest Rate (in hundredths)																										6.15%	7.86%	6.25%	6.25%	8.25%	8.25%	6.625%	6.625%	7.875%	7.875%	8.25%	8.25%	8.125%	8.125%	7.125%	0.00%	7.125%	7.125%	8.50%	8.50%	9.25%	0.00%	8.75%	8.75%	7.875%	7.875%	6.73%	6.73%	8.40%	8.40%	9.00%	9.00%	7.00%	7.00%	6.80%	6.80%	7.68%	7.68%	7.45%	7.45%	7.05%	7.05%	3.095%	[1]	3.175%	[1]	7.86%	7.93%	0.00%	8.05%	6.33%
Long term debt weighted average interest rate (in hundredths)	7.85%
Senior Notes [Abstract]
Aggregate principal amount of debt under registered offering																			250,000,000	600,000,000
Issue price expressed as a percentage of principal amount (in hundredths)															100.00%				104.25%	100.00%
Effective interest cost (in hundredths)																			6.551%											10.855%
Net proceeds from offering															489,600,000				255,900,000	588,100,000
Private offering of debt related to the Merger			3,200,000,000
Transaction Escrow related to the Merger			125,500,000
Excess received of the special cash payment and the initial purchasers' discount received related to the Merger			53,000,000
Aggregate principal amount agreed to be purchased											400,000,000	75,700,000	49,500,000	59,300,000								500,000,000
Amount of consideration for purchase of notes											446,000,000		54,000,000								154,700,000
Losses on early extinguishment of debt	(90,363,000)	0	0							(69,000,000)											(19,300,000)
Gain (Loss) on repurchase of debt instrument										2,100,000
Debt instrument repurchase amount										78,100,000
Credit Agreement [Abstract]
Repayment of the outstanding principal balance, quarterly installments amount																14,375,000
First payment date of the quarterly repayment of the outstanding principal balance																Mar. 31, 2012
Interest rate margin for Base Rate borrowings, minimum (in hundredths)																0.875%
Interest rate margin for Base Rate borrowings, maximum (in hundredths)																2.875%
Interest rate margin for LIBOR borrowings, minimum (in hundredths)																1.875%
Interest rate margin for LIBOR borrowings, maximum (in hundredths)																3.875%
Initial pricing for LIBOR based borrowings (in hundredths)																2.875%
Maximum permitted leverage ratio																4.5
Number of debt facilities	3
Credit facilities [Abstract]
Interest Rate (in hundredths)									0.625%
Line of credit initiation date	Mar. 23, 2010
Line of credit facility expiration date	Jan. 01, 2014
Line of credit facility maximum borrowing capacity					40,000,000	190,000,000	20,000,000	20,000,000	750,000,000
Number of letters of credit					2
Exercised extension of commitment					100,000,000
Date that the Bank to exercise its option to extend the commitments					September 20, 2012
Principal payments by year [Abstract]
Principal Payments 2013	560,550,000
Principal Payments 2014	257,916,000
Principal Payments 2015	732,746,000
Principal Payments 2016	345,466,000
Principal Payments 2017	1,041,186,000
Other Obligation [Abstract]
Number of properties contributed to qualified defined benefit pension plan		4
Fair value of pension plan contribution				58,100,000
Number years company entered into leases for the contributed properties		15 years
Annual rent expense for the contributed properties		5,800,000
Initial obligation recorded as a result of contribution and leaseback of the properties		58,100,000
Long term portion of initial obligation		57,500,000
Current portion of initial obligation		600,000
Sale and leaseback term, minimum	12 years
Sale and leaseback term, maximum (in years)	23 years
Finance Lease Obligations, Future Minimum Payments [Abstract]
2013	5,339,000
2014	5,170,000
2015	5,276,000
2016	5,407,000
2017	5,550,000
Thereafter	54,274,000
Total future payments	81,016,000
Capital Lease Obligations, Future Minimum Payments [Abstract]
2013	3,055,000
2014	3,107,000
2015	3,161,000
2016	3,216,000
2017	3,273,000
Thereafter	22,387,000
Total future payments	38,199,000
Less: Amounts representing interest	(11,603,000)
Present Value of minimum lease payments	$ 26,596,000

[1] Represents borrowings under the Credit Agreement with Co Bank.