|**RECEIVABLES (Tables)**                                   | 12 Months Ended                                                                                                                                                                                           
|---------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|
|**Receivables [Abstract]**                                 |                                                                                                                                                                                                           
|Schedule of Receivables                                    | Receivables are summarized below:20182017(In millions)Accounts receivable$468$368Unbilled costs and accrued earnings on cost-plus contracts269258737626Less allowances for collection losses(2)(3)$735$623
|                                                          
|                                                           |                                                                                                                                                                                                           
|                                                           | 2018                                                                                                                                                                                                      
|                                                           |                                                                                                                                                                                                           
|                                                           | (In millions)                                                                                                                                                                                             
|Accounts receivable                                        | $                                                                                                                                                                                                         
|Unbilled costs and accrued earnings on cost-plus contracts | 269                                                                                                                                                                                                       
|                                                           | 737                                                                                                                                                                                                       
|Less allowances for collection losses                      | (2                                                                                                                                                                                                        
|                                                           | $                                                                                                                                                                                                         

X- ReferencesNo definition available.
+ Details**Name:**
us-gaap_ReceivablesAbstract**Namespace Prefix:**
us-gaap_**Data Type:**
xbrli:stringItemType**Balance Type:**
na**Period Type:**
duration X- DefinitionTabular disclosure of the various types of trade accounts and notes receivable and for each the gross carrying value, allowance, and net carrying value as of the balance sheet date. Presentation is categorized by current, noncurrent and unclassified receivables.
+ ReferencesReference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.3,4) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682
+ Details**Name:**
us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock**Namespace Prefix:**
us-gaap_**Data Type:**
nonnum:textBlockItemType**Balance Type:**
na**Period Type:**
duration