XML 34 R32.htm IDEA: XBRL DOCUMENT v2.3.0.15

Pension And Other Postretirement Benefits (Tables)

9 Months Ended

Sep. 30, 2011

Pension And Other Postretirement Benefits

Components Of Net Periodic Benefit Cost

		Third quarter  ended September 30,								Nine months  ended September 30,
Pension benefits		2011				2010				2011				2010
Service cost		$	41			$	38			$	123			$	111
Interest cost			169				170				509				510
Expected return on plan assets			(202	)			(195	)			(605	)			(586	)
Amortization of prior service cost			5				4				14				12
Recognized net actuarial loss			63				46				187				135
Net periodic benefit cost		$	76			$	63			$	228			$	182
		Third quarter  ended September 30,								Nine months  ended September 30,
Other postretirement benefits		2011				2010				2011				2010
Service cost		$	5			$	5			$	13			$	15
Interest cost			40				44				119				131
Expected return on plan assets			(1	)			(2	)			(2	)			(5	)
Amortization of prior service benefit			(5	)			(4	)			(13	)			(11	)
Recognized net actuarial loss			7				8				20				24
Settlements			—				—				—				(3	)
Net periodic benefit cost		$	46			$	51			$	137			$	151

X

- Definition

Schedule Of Components of Net Periodic Benefit Cost [Text Block]

+ 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