|**Operating Leases, Commitments and Contingencies, and Guarantees (Tables)**   | 12 Months Ended                                                                                                                                                                           
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|**Operating Leases, Commitments and Contingencies, and Guarantees [Abstract]** |                                                                                                                                                                                           
|Future minimum lease payments and sublease receipts                            | Future Minimum Lease Payments and Sublease Receipts(In millions)Future Minimum Lease PaymentsFuture Minimum Sublease Receipts2013$39$2201433—201525—201624—201717—Thereafter72—Total$210$2
|                                                                              
|                                                                               |                                                                                                                                                                                           
|(In millions)                                                                  | Future Minimum Lease Payments                                                                                                                                                             
|2013                                                                           | $                                                                                                                                                                                         
|2014                                                                           | 33                                                                                                                                                                                        
|2015                                                                           | 25                                                                                                                                                                                        
|2016                                                                           | 24                                                                                                                                                                                        
|2017                                                                           | 17                                                                                                                                                                                        
|Thereafter                                                                     | 72                                                                                                                                                                                        
|Total                                                                          | $                                                                                                                                                                                         

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