| **Employee Retirement Benefits**                      | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
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| **Compensation and Retirement Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| Employee Retirement Benefits                          | EMPLOYEE RETIREMENT BENEFITSThe following summarizes the components of net periodic costs for our qualified and supplemental pension plans:(In millions) Three months ended June 30, Six months ended June 30,  2014 2013 2014 2013Service cost $3 $3 $5 $6Interest cost 3 3 7 6Expected return on plan assets (4) (4) (8) (8)Amortization of actuarial loss and prior service cost 0 3 1 5Net periodic benefit cost $2 $5 $5 $9         See our 2013 Annual Report on Form 10-K, Item 8, Note 13, Employee Retirement Benefits, Page 148, for information on our retirement benefits. We made matching contributions of $2 million to our 401(k) and Top Hat savings plans during both the second quarter of 2014 and 2013 and contributions of $6 million and $5 million for the first six months of 2014 and 2013, respectively.  We contributed $5 million to our qualified pension plan during the first quarter of 2014. We do not anticipate further contributions to our qualified pension plan during the remainder of 2014. |

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| - Definition
The entire disclosure for pension and other postretirement benefits.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -URI http://asc.fasb.org/topic&trid=2235017
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