| **Inventories (Tables)**      | 12 Months Ended                                                                                                                                                                                                                                                                                |
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| **Inventory, Net [Abstract]** |                                                                                                                                                                                                                                                                                           |
| Inventories                   | Inventories are summarized below: 2016 2015     (In millions)Unbilled costs and accrued earnings on fixed-price contracts$512 $463Finished products129 100Work in process123 256Raw materials and supplies200 196 $964 $1,015 |

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| - References
No definition available.
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| - Definition
Tabular disclosure of the carrying amount as of the balance sheet date of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.
+ References
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