Annual report pursuant to Section 13 and 15(d)

COMPANY-SPONSORED EMPLOYEE BENEFIT PLANS - Funded Status as of the Respective Measurement Dates in Each Year and the Amounts Recognized in Balance Sheet (Detail)

v3.8.0.1
COMPANY-SPONSORED EMPLOYEE BENEFIT PLANS - Funded Status as of the Respective Measurement Dates in Each Year and the Amounts Recognized in Balance Sheet (Detail) - USD ($)
$ in Millions
 3 Months Ended 12 Months Ended
Dec. 31, 2016
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]        
Payment for Pension and Other Postretirement Benefits $ 685 $ 7,794 $ 2,668 $ 1,229
Funded Status:        
Fair value of plan assets 0 8 0  
Pension Benefits        
Defined Benefit Plan Disclosure [Line Items]        
Payment for Pension and Other Postretirement Benefits     22  
Pension Benefits | U.S. Pension Benefits        
Funded Status:        
Fair value of plan assets 31,215 41,932 31,215 28,887
Benefit obligation (41,069) (45,847) (41,069) (36,846)
Funded status recognized at December 31 (9,854) (3,915) (9,854)  
Funded Status Recognized in our Balance Sheet:        
Other non-current assets 0 284 0  
Other current liabilities (17) (18) (17)  
Pension and postretirement benefit obligations (9,837) (4,181) (9,837)  
Net liability at December 31 (9,854) (3,915) (9,854)  
Amounts Recognized in AOCI:        
Unrecognized net prior service cost (1,074) (880) (1,074)  
Unrecognized net actuarial gain (loss) (4,107) (4,277) (4,107)  
Gross unrecognized cost at December 31 (5,181) (5,157) (5,181)  
Deferred tax assets (liabilities) at December 31 1,948 1,840 1,948  
Net unrecognized cost at December 31 (3,233) (3,317) (3,233)  
Pension Benefits | International Pension Benefits        
Funded Status:        
Fair value of plan assets 1,092 1,333 1,092 1,014
Benefit obligation (1,425) (1,651) (1,425) (1,219)
Funded status recognized at December 31 (333) (318) (333)  
Funded Status Recognized in our Balance Sheet:        
Other non-current assets 28 35 28  
Other current liabilities (3) (5) (3)  
Pension and postretirement benefit obligations (358) (348) (358)  
Net liability at December 31 (333) (318) (333)  
Amounts Recognized in AOCI:        
Unrecognized net prior service cost (3) (2) (3)  
Unrecognized net actuarial gain (loss) (150) (126) (150)  
Gross unrecognized cost at December 31 (153) (128) (153)  
Deferred tax assets (liabilities) at December 31 37 31 37  
Net unrecognized cost at December 31 (116) (97) (116)  
Postemployment Retirement Benefits | U.S. Pension Benefits        
Funded Status:        
Fair value of plan assets 15 183 15 130
Benefit obligation (2,730) (2,792) (2,730) $ (2,673)
Funded status recognized at December 31 (2,715) (2,609) (2,715)  
Funded Status Recognized in our Balance Sheet:        
Other non-current assets 0 0 0  
Other current liabilities (216) (77) (216)  
Pension and postretirement benefit obligations (2,499) (2,532) (2,499)  
Net liability at December 31 (2,715) (2,609) (2,715)  
Amounts Recognized in AOCI:        
Unrecognized net prior service cost (36) (29) (36)  
Unrecognized net actuarial gain (loss) (80) (195) (80)  
Gross unrecognized cost at December 31 (116) (224) (116)  
Deferred tax assets (liabilities) at December 31 44 69 44  
Net unrecognized cost at December 31 $ (72) $ (155) $ (72)