| **Leases**            | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
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| **Leases [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| Leases                | LEASES We lease our offices and other property through operating leases.  Rental expense is charged to operations as incurred.  For 2015, 2014 and 2013, total rental expense for operating leases was $16 million, $17 million and $17 million, respectively.  At December 31, 2015, minimum payments for operating leases having initial non-cancelable terms in excess of one year were as follows: (Millions of dollars) 2016$15201714201813201913202012Thereafter16Total$83   |

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No definition available.
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| - Definition
The entire disclosure for lessee entity's leasing arrangements including, but not limited to, all of the following: (a.) The basis on which contingent rental payments are determined, (b.) The existence and terms of renewal or purchase options and escalation clauses, (c.) Restrictions imposed by lease agreements, such as those concerning dividends, additional debt, and further leasing.
+ References
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