XML 61 R30.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Pension and Other Postretirement Benefits (Tables) | 3 Months Ended
--- | ---
Mar. 31, 2015
Compensation and Retirement Disclosure [Abstract] |
Components of Net Periodic Benefit Cost | The components of net periodic benefit cost were as follows:
|  | Pension benefits |  |  | Other postretirement benefits |
First quarter ended March 31, |  | 2015 |  |  | 2014 |  |  | 2015 |  |  | 2014 |
Service cost |  | $ | 44 |  |  | $ | 41 |  |  | $ | 3 |  |  | $ | 4 |
Interest cost |  |  | 144 |  |  |  | 160 |  |  |  | 23 |  |  |  | 29 |
Expected return on plan assets |  |  | (188 | ) |  |  | (193 | ) |  |  | — |  |  |  | — |
Recognized net actuarial loss |  |  | 118 |  |  |  | 97 |  |  |  | 4 |  |  |  | 3 |
Amortization of prior service cost (benefit) |  |  | 4 |  |  |  | 4 |  |  |  | (9 | ) |  |  | (5 | )
Settlement* |  |  | 1 |  |  |  | — |  |  |  | — |  |  |  | — |
Special termination benefits* |  |  | 2 |  |  |  | — |  |  |  | — |  |  |  | — |
Net periodic benefit cost |  | $ | 125 |  |  | $ | 109 |  |  | $ | 21 |  |  | $ | 31 |
* | 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. + References No definition available. + Details
Name: | aa_ScheduleOfComponentsOfNetPeriodicBenefitCostTextBlock
Namespace Prefix: | aa_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_CompensationAndRetirementDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration