XML 44 R35.htm IDEA: XBRL DOCUMENT v3.3.0.814
Accumulated Other Comprehensive Loss - Summary of Changes in Accumulated Other Comprehensive Loss by Component (Detail) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2015
Sep. 30, 2014
Sep. 30, 2015
Sep. 30, 2014
Pension and other postretirement benefits        
Total Other comprehensive income (loss) $ 120 $ 122 $ 226 $ 214
Foreign currency translation        
Other comprehensive loss (1,188) (1,000) (2,166) (464)
Available-for-sale securities        
Other comprehensive (loss) income (2) (1) (2)  
Cash flow hedges        
Total Other comprehensive income (loss) 215 (14) 581 (11)
Energy Contracts [Member]        
Cash flow hedges        
Total Other comprehensive income (loss) before reclassifications, net of tax 3 (28) (8) (10)
Alcoa [Member]        
Pension and other postretirement benefits        
Balance at beginning of period (3,500) (3,441) (3,601) (3,532)
Unrecognized net actuarial loss and prior service cost/benefit 46 96 (30) 33
Tax (expense) benefit (10) (33) 18 (8)
Total Other comprehensive (loss) income before reclassifications, net of tax 36 63 (12) 25
Amortization of net actuarial loss and prior service cost/benefit 116 97 345 296
Tax expense (41) (34) (121) (104)
Total amount reclassified from Accumulated other comprehensive loss, net of tax 75 63 224 192
Total Other comprehensive income (loss) 111 126 212 217
Balance at end of period (3,389) (3,315) (3,389) (3,315)
Foreign currency translation        
Balance at beginning of period (1,606) 569 (846) 179
Other comprehensive loss (889) (774) (1,649) (384)
Balance at end of period (2,495) (205) (2,495) (205)
Available-for-sale securities        
Balance at beginning of period   3   2
Other comprehensive (loss) income (2) (1) (2)  
Balance at end of period (2) 2 (2) 2
Cash flow hedges        
Balance at beginning of period 140 (299) (230) (308)
Net change from periodic revaluations 288 (35) 792 (31)
Tax (expense) benefit (79) 11 (235) 7
Total Other comprehensive income (loss) before reclassifications, net of tax 209 (24) 557 (24)
Net amount reclassified to earnings 6 6 35 17
Tax expense (1) (1) (8) (3)
Total amount reclassified from Accumulated other comprehensive income (loss), net of tax 5 5 27 14
Total Other comprehensive income (loss) 214 (19) 584 (10)
Balance at end of period 354 (318) 354 (318)
Alcoa [Member] | Aluminum Contracts [Member]        
Cash flow hedges        
Net amount reclassified to earnings 3 7 26 18
Alcoa [Member] | Energy Contracts [Member]        
Cash flow hedges        
Net amount reclassified to earnings     4  
Alcoa [Member] | Foreign Exchange Contracts [Member]        
Cash flow hedges        
Net amount reclassified to earnings 2 (1) 3 (2)
Alcoa [Member] | Interest Rate Contracts [Member]        
Cash flow hedges        
Net amount reclassified to earnings     1 1
Alcoa [Member] | Nickel Contracts [Member]        
Cash flow hedges        
Net amount reclassified to earnings 1   1  
Noncontrolling Interests [Member]        
Pension and other postretirement benefits        
Balance at beginning of period (59) (50) (64) (51)
Unrecognized net actuarial loss and prior service cost/benefit 10 (9) 13 (9)
Tax (expense) benefit (1) 3 (1) 3
Total Other comprehensive (loss) income before reclassifications, net of tax 9 (6) 12 (6)
Amortization of net actuarial loss and prior service cost/benefit   3 4 5
Tax expense   (1) (2) (2)
Total amount reclassified from Accumulated other comprehensive loss, net of tax   2 2 3
Total Other comprehensive income (loss) 9 (4) 14 (3)
Balance at end of period (50) (54) (50) (54)
Foreign currency translation        
Balance at beginning of period (569) 36 (351) (110)
Other comprehensive loss (299) (226) (517) (80)
Balance at end of period (868) (190) (868) (190)
Cash flow hedges        
Balance at beginning of period (6) (8) (2) (2)
Net change from periodic revaluations 1 7 (4) (2)
Tax (expense) benefit   (2) 1 1
Total Other comprehensive income (loss) before reclassifications, net of tax 1 5 (3) (1)
Total Other comprehensive income (loss) 1 5 (3) (1)
Balance at end of period $ (5) $ (3) $ (5) $ (3)