| **Income Taxes**                     | 3 Months Ended                                                                                                                                                                                                                                                                                           |
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| **Income Tax Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                     |
| Income Taxes                         | Income Taxes The Provision for income taxes reflects an estimated annual tax rate of 27 percent for the first quarter of 2013 and 2012.  The first quarter 2013 estimated annual tax rate of 27 percent excludes a benefit of $7 million reflecting the impact of the American Taxpayer Relief Act. |

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| - Definition
The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.
+ References
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