| **Long-Term Debt (Tables)**   | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
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| **Long-Term Debt [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| Long-Term Debt                | The activity in our long-term debt from December 31, 2012 to June 30, 2013 is summarized as follows:        Six months ended                     June 30, 2013          Interest                            Rate at    December 31,    Payments    New      June 30,  June 30,($ in thousands)  2012    and Retirements  Borrowings      2013  2013 *                                Senior Unsecured Debt$8,919,696  $       (1,533,880)   $      750,000     $8,135,816  7.96%                                Industrial Development                                 Revenue Bonds  13,550                         -                    -      13,550  6.33%                                Rural Utilities Service                                Loan Contracts  9,322                     (194)                    -      9,128  6.15%                              TOTAL LONG-TERM DEBT$8,942,568   $       (1,534,074)   $      750,000    $8,158,494  7.95%                                Less: Debt (Discount)/Premium                 (71)                                       333      Less: Current Portion          (560,550)                              (257,905)                                    $       8,381,947                $           7,900,922                                  * Interest rate includes amortization of debt issuance costs and debt premiums or discounts.  The interest rates at June 30, 2013 represent a weighted average of multiple issuances.                                                                                                                                                                                                                                                                                                    |
| Senior Unsecured Debt         | Additional information regarding our Senior Unsecured Debt is as follows:($ in thousands)June 30, 2013  December 31, 2012    Principal    Interest      Principal    Interest      Outstanding    Rate      Outstanding    Rate                              Senior Notes and   Debentures Due:                             1/15/2013$-    -    $502,658    6.250%     5/1/2014  200,000    8.250%      200,000    8.250%     3/15/2015  105,026    6.625%      300,000    6.625%     4/15/2015  96,872    7.875%      374,803    7.875%     10/14/2016 *  488,750    3.075% (Variable)      517,500    3.095% (Variable)     4/15/2017  606,874    8.250%      1,040,685    8.250%     10/1/2018  582,739    8.125%      600,000    8.125%     3/15/2019  434,000    7.125%      434,000    7.125%     4/15/2020  1,021,505    8.500%      1,100,000    8.500%     7/1/2021  500,000    9.250%      500,000    9.250%     4/15/2022  500,000    8.750%      500,000    8.750%     1/15/2023  850,000    7.125%      850,000    7.125%     4/15/2024  750,000    7.625%      -    -     11/1/2025  138,000    7.000%      138,000    7.000%     8/15/2026  1,739    6.800%      1,739    6.800%     1/15/2027  345,858    7.875%      345,858    7.875%     8/15/2031  945,325    9.000%      945,325    9.000%     10/1/2034  628    7.680%      628    7.680%     7/1/2035  125,000    7.450%      125,000    7.450%     10/1/2046  193,500    7.050%      193,500    7.050%      7,885,816            8,669,696                                    Subsidiary Senior Notes   and Debentures Due:                             2/15/2028  200,000    6.730%      200,000    6.730%     10/15/2029  50,000    8.400%      50,000    8.400%                              Total$8,135,816    7.77% **    $8,919,696    7.69% **                              *      Represents borrowings under the Credit Agreement with CoBank.**    Interest rate represents a weighted average of the stated interest rates of multiple issuances. |
| Debt Maturities by Year       | Our principal payments for the next five years are as follows as of June 30, 2013:     Principal($ in thousands)  Payments        2013 (remaining six months)$28,9482014$257,9162015$259,8402016$345,4662017$607,3752018$583,273                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |

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| - Definition
Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.
+ References
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| - Definition
Tabular disclosure of information pertaining to short-term and long-debt instruments or arrangements, including but not limited to identification of terms, features, collateral requirements and other information necessary to a fair presentation.
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| - Definition
Tabular disclosure of the combined aggregate amount of maturities and sinking fund requirements for all long-term borrowings for each of the five years following the date of the latest balance sheet date presented.
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