XML 37 R32.htm IDEA: XBRL DOCUMENT
v3.3.0.814

Pension and Other Postretirement Benefits (Tables) | 9 Months Ended
--- | ---
Sep. 30, 2015
Compensation and Retirement Disclosure [Abstract] |
Components of Net Periodic Benefit Cost | The components of net periodic benefit cost were as follows:
|  | Third quarter ended September 30, |  |  | Nine months ended September 30, |
Pension benefits |  | 2015 |  |  | 2014 |  |  | 2015 |  |  | 2014 |
Service cost |  | $ | 44 |  |  | $ | 42 |  |  | $ | 132 |  |  | $ | 125 |
Interest cost |  |  | 144 |  |  |  | 157 |  |  |  | 433 |  |  |  | 476 |
Expected return on plan assets |  |  | (189 | ) |  |  | (198 | ) |  |  | (566 | ) |  |  | (586 | )
Recognized net actuarial loss |  |  | 117 |  |  |  | 97 |  |  |  | 352 |  |  |  | 292 |
Amortization of prior service cost |  |  | 4 |  |  |  | 5 |  |  |  | 12 |  |  |  | 14 |
Settlements* |  |  | 13 |  |  |  | 18 |  |  |  | 14 |  |  |  | 18 |
Curtailments* |  |  | 9 |  |  |  | — |  |  |  | 9 |  |  |  | — |
Special termination benefits* |  |  | — |  |  |  | — |  |  |  | 12 |  |  |  | — |
Net periodic benefit cost |  | $ | 142 |  |  | $ | 121 |  |  | $ | 398 |  |  | $ | 339 |
* | Except for Settlements of $2 in both the third quarter and nine months ended September 30, 2015, these amounts were recorded in Restructuring and other charges on the accompanying Statement of Consolidated Operations (see Note D).
|  | Third quarter ended September 30, |  |  | Nine months ended September 30, |
Other postretirement benefits |  | 2015 |  |  | 2014 |  |  | 2015 |  |  | 2014 |
Service cost |  | $ | 4 |  |  | $ | 4 |  |  | $ | 11 |  |  | $ | 12 |
Interest cost |  |  | 23 |  |  |  | 28 |  |  |  | 69 |  |  |  | 86 |
Recognized net actuarial loss |  |  | 4 |  |  |  | 4 |  |  |  | 13 |  |  |  | 10 |
Amortization of prior service benefit |  |  | (9 | ) |  |  | (6 | ) |  |  | (28 | ) |  |  | (15 | )
Curtailments* |  |  | (5 | ) |  |  | — |  |  |  | (6 | ) |  |  | — |
Special termination benefits* |  |  | — |  |  |  | — |  |  |  | 1 |  |  |  | — |
Net periodic benefit cost |  | $ | 17 |  |  | $ | 30 |  |  | $ | 60 |  |  | $ | 93 |
* | These amounts were recorded in Restructuring and other charges on the accompanying Statement of Consolidated Operations (see Note D).

X
- Definition Schedule of components of net periodic benefit cost table text block. + References No definition available. + Details
Name: | aa_ScheduleOfComponentsOfNetPeriodicBenefitCostTextBlock
Namespace Prefix: | aa_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_CompensationAndRetirementDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration