| **Retirement Plans (Tables)**                         | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 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| **Compensation and Retirement Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    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| Net Periodic Benefit Cost                             | The following tables provide the components of net periodic benefit cost:  Pension Benefits    Pension Benefits  For the three months ended      For the nine months ended    September 30,    September 30,  2011    2010      2011  2010($ in thousands)                    Components of net periodic pension benefit cost                    Service cost $          9,615  $8,994    $28,844   $         12,212Interest cost on projected benefit obligation           21,172                21,601                 63,516              46,364Expected return on plan assets          (25,589)               (23,262)                (76,766)             (46,561)Amortization of prior service cost /(credit)                 (50)                      (49)                     (150)                  (149)Amortization of unrecognized loss             4,435                  7,048                 13,306              20,545Net periodic pension benefit cost $          9,583  $14,332    $28,750   $         32,411                        Postretirement Benefits    Postretirement Benefits  Other Than Pensions (OPEB)    Other Than Pensions (OPEB)  For the three months ended      For the nine months ended  September 30,      September 30,  2011    2010      2011  2010($ in thousands)                    Components of net periodic postretirement benefit cost                    Service cost $          4,206  $3,842    $12,662   $           4,041Interest cost on projected benefit obligation             5,986                  6,241                 18,642              11,499Expected return on plan assets                 (79)                    (113)                     (242)                  (330)Amortization of prior service cost/(credit)            (2,552)                 (1,932)                  (7,651)               (5,790)Amortization of unrecognized loss                607                     528                   3,604                3,690Net periodic postretirement benefit cost $          8,168  $8,566    $27,015   $         13,110                     |

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| - Definition
Tabular disclosure of one or more of the entity's defined benefit pension plans or one or more other defined benefit postretirement plans, separately for pension plans and other postretirement benefit plans including the entity's schedule of fair value of plan assets for defined benefit or other postretirement plans.
+ References
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