Quarterly report pursuant to Section 13 or 15(d)

EMPLOYEE BENEFIT PLANS - Additional Information (Detail)

v2.4.0.8
EMPLOYEE BENEFIT PLANS - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
6 Months Ended 9 Months Ended 9 Months Ended 3 Months Ended 9 Months Ended 3 Months Ended 12 Months Ended 9 Months Ended 3 Months Ended 6 Months Ended 6 Months Ended
Jun. 30, 2014
Sep. 30, 2014
Dec. 31, 2013
Employees
Sep. 30, 2014
Defined Benefit Pension Plan
Sep. 30, 2014
Defined Benefit Postretirement Medical Benefit Plan
Sep. 30, 2014
Defined Benefit Postretirement Medical Benefit Plan
Dec. 31, 2013
Defined Benefit Postretirement Medical Benefit Plan
Sep. 30, 2014
Multiemployer Plans, Pension [Member]
Dec. 31, 2013
Multiemployer Plans, Pension [Member]
Dec. 31, 2014
Subsequent Event [Member]
Dec. 31, 2014
Subsequent Event [Member]
Dec. 31, 2014
Subsequent Event [Member]
Defined Benefit Postretirement Medical Benefit Plan
Sep. 30, 2014
Non-National Master Agreement (Non-NMA) [Member]
Employees
Jun. 30, 2014
Non-National Master Agreement (Non-NMA) [Member]
Jun. 30, 2014
National Master Agreement (NMA) [Member]
Jun. 30, 2014
National Master Agreement (NMA) [Member]
Sep. 30, 2014
National Master Agreement (NMA) [Member]
Employees
Jun. 30, 2014
remeasurement of postretirement obligation [Member]
Jun. 30, 2014
defined benefit plan settlement losses [Member]
National Master Agreement (NMA) [Member]
Jun. 30, 2014
partial plan curtailment [Member]
Defined Benefit Plan Disclosure [Line Items]                                        
other employees under collective bargaining agreements affected by changes in healthcare benefits                         16,000              
Amount contributed to company- sponsored benefit plans       $ 71   $ 92                            
Estimated future employer contributions to defined benefit plan, current fiscal year       49   36                            
Number of employees under a national master agreement and various supplemental agreements with local unions affiliated with Teamsters     253,000                                  
Majority of ground mechanics not employed under agreements     3,100                                  
Defined Benefit Plan, Benefits Paid                             278          
Full-time employees affected by change in healthcare benefits                                 36,000      
part-time employees affected by changes in healthcare benefits                                 73,000      
Multiemployer Plans, Withdrawal Obligation, Present Value               879 884                      
Multi-employer Plans, Withdrawal Obligation, Fair Value Disclosure               850 783                      
Number of pilots under a collective bargaining agreement with the Independent Pilots Association     2,600                                  
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements and Curtailments         0 (320)             31     1,066   746 208 112
DefinedBenefitPlanRecognizedNetGainLossDuetoSettlementsandCurtailmentsAfterTax 665                                      
Settlement payments to fund for assumption of postretirement benefit obligation 2,271                         276 1,995 1,995        
CashTaxBenefitDueToSettlementofBenefitObligation   563               291                    
ChangeInPostRetirementBenefitandAOCI 13                                      
Defined Benefit Plan, Curtailments   946                 1,153                  
Defined Benefit Plan, Plans with Benefit Obligations in Excess of Plan Assets, Aggregate Benefit Obligation         $ 2,745 $ 2,745 $ 3,691         $ 2,538