XML 107 R93.htm IDEA: XBRL DOCUMENT
v3.6.0.2

Segment and Geographical Area Information, Narrative (Details) | 12 Months Ended
--- | ---
Dec. 31, 2016 productionfacilities customer | Dec. 31, 2015 customer | Dec. 31, 2014 customer
Segment Reporting Information |  |  |
Percentage of Employees Covered by Collective Bargaining Agreements | 63.00% |  |
Percentage of Employees Covered by Collective Bargaining Agreements Expiring Within One Year | 6.00% |  |
United States |  |  |
Segment Reporting Information |  |  |
Number of production facilities | productionfacilities | 11 |  |
Canada |  |  |
Segment Reporting Information |  |  |
Number of production facilities | productionfacilities | 1 |  |
Customer Concentration Risk | Net sales | Largest Customer | Fabricated Products |  |  |
Segment Reporting Information |  |  |
Concentration risk, percentage | 26.00% | 25.00% | 22.00%
Number of Customers | customer | 1 | 1 | 1
Customer Concentration Risk | Net sales | Second Largest Customer | Fabricated Products |  |  |
Segment Reporting Information |  |  |
Concentration risk, percentage | 10.00% | 10.00% | 10.00%
Customer Concentration Risk | Trade Receivables | Largest Customer |  |  |
Segment Reporting Information |  |  |
Concentration risk, percentage | 18.00% |  |
Customer Concentration Risk | Trade Receivables | Second Largest Customer |  |  |
Segment Reporting Information |  |  |
Concentration risk, percentage | 12.00% |  |
Customer Concentration Risk | Trade Receivables | Second Largest Customer | Fabricated Products |  |  |
Segment Reporting Information |  |  |
Number of Customers | customer | 2 |  |
Customer Concentration Risk | Trade Receivables | Largest Customer (number 1) [Member] |  |  |
Segment Reporting Information |  |  |
Concentration risk, percentage |  | 17.00% |

X
- Definition Number of Production Facilities. + References No definition available. + Details
Name: | kalu_NumberOfProductionFacilities
Namespace Prefix: | kalu_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of Customers + References No definition available. + Details
Name: | kalu_NumberofCustomers
Namespace Prefix: | kalu_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of Employees Covered by Collective Bargaining Agreements + References No definition available. + Details
Name: | kalu_PercentageofEmployeesCoveredbyCollectiveBargainingAgreements
Namespace Prefix: | kalu_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percentage of Employees Covered by Collective Bargaining Agreements Expiring Within One Year + References No definition available. + Details
Name: | kalu_PercentageofEmployeesCoveredbyCollectiveBargainingAgreementsExpiringWithinOneYear
Namespace Prefix: | kalu_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13531-108611 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6404-108592 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13537-108611 + Details
Name: | us-gaap_ConcentrationRiskPercentage1
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_SegmentReportingInformationLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_StatementGeographicalAxis=country_US
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementGeographicalAxis=country_CA
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CustomerConcentrationRiskMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_SalesRevenueNetMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorCustomersAxis=kalu_LargestCustomerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=kalu_FabricatedProductsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorCustomersAxis=kalu_SecondLargestCustomerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_AccountsReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorCustomersAxis=kalu_LargestCustomernumber1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |