v2.3.0.15

Subsequent Events (Details) (USD $)	3 Months Ended
	Dec. 31, 2011
Subsequent Events (Textuals) [Abstract]
Cash dividend declared	$ 0.24

X

- Definition

Subsequent Events.

+ Details

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Namespace Prefix:	kalu
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

+ Details

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Namespace Prefix:	us-gaap
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Balance Type:	na
Period Type:	duration