XML 48 R37.htm IDEA: XBRL DOCUMENT
v3.20.2

Basis of Presentation, Economic Conditions and Recent Accounting Pronouncements - Additional Information (Details) - USD ($) | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2020 | Sep. 30, 2020 | May 01, 2020 | Apr. 28, 2020
Significant Accounting Policies [Line Items] |  |  |  |
Net sales from performance obligations | $ 15,000,000.0 | $ 15,000,000.0 |  |
Accounting Standards Update (“ASU”) No. 2016-13 |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Change in Accounting Principle, Accounting Standards Update, Adopted | true | true |  |
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect | true | true |  |
ASU No. 2018-15 |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Change in Accounting Principle, Accounting Standards Update, Adopted | true | true |  |
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect | true | true |  |
Change in Accounting Principle, Accounting Standards Update, Transition Option Elected [Extensible List] |  | us-gaap:AccountingStandardsUpdate201815ProspectiveMember |  |
Senior Notes Due 2025 | Senior Notes |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Debt principal amount | $ 350,000,000.0 | $ 350,000,000.0 | $ 50,000,000.0 | $ 300,000,000.0

X
- Definition Significant accounting policies [Line Items] + References No definition available. + Details
Name: | kalu_SignificantAccountingPoliciesLineItems
Namespace Prefix: | kalu_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Indicates (true false) whether accounting standards update was adopted. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 10 -Section 65 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121329987&loc=SL120154346-209984 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 65 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121322162&loc=SL121327923-165333 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22499-107794 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 20 -Section 65 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=121483254&loc=SL120254523-199619 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121370832&loc=SL117420844-207641 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 10 -Section 65 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121646688&loc=SL121648383-210437 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 10 -Section 65 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121646688&loc=SL121648383-210437 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 926 -SubTopic 20 -Section 65 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=120154821&loc=SL120154904-197079 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 926 -SubTopic 20 -Section 65 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=120154821&loc=SL120154904-197079 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 10 -Section 65 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121646688&loc=SL120320025-210437 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 10 -Section 65 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121646688&loc=SL120320025-210437 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 65 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=120240428&loc=SL120254526-165497 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121370832&loc=SL117420844-207641 Reference 14: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 65 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121322162&loc=SL121327923-165333 Reference 15: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 65 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121322162&loc=SL121327923-165333 Reference 16: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 10 -Section 65 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121646688&loc=SL120254519-210437 Reference 17: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 65 -Paragraph 8 -Subparagraph (a) + Details
Name: | us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateAdopted
Namespace Prefix: | us-gaap_
Data Type: | xbrli:booleanItemType
Balance Type: | na
Period Type: | instant

X
- Definition Indicates (true false) whether effect from applying amendment to accounting standards is immaterial. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section S99 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=112272810&loc=d3e31010-122693 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 65 -Paragraph 15 -Subparagraph (g)(2) -URI http://asc.fasb.org/extlink&oid=121322162&loc=SL121327923-165333 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 10 -Section 65 -Paragraph 4 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=121646688&loc=SL121648383-210437 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22499-107794 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 65 -Paragraph 8 -Subparagraph (e)(3) + Details
Name: | us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateImmaterialEffect
Namespace Prefix: | us-gaap_
Data Type: | xbrli:booleanItemType
Balance Type: | na
Period Type: | instant

X
- Definition Indicates transition method applied for adoption of amendment to accounting standards. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 65 -Paragraph 4 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=109261464&loc=SL109261606-128450 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 40 -Section 65 -Paragraph 3 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=120431994&loc=SL118172731-207502 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 405 -SubTopic 20 -Section 65 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=77997009&loc=SL77997016-210199 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 40 -Section 65 -Paragraph 3 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=120431994&loc=SL118172731-207502 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 10 -Section 65 -Paragraph 1 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=121329987&loc=SL77916155-209984 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 65 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=98513396&loc=SL94080479-196980 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (k) -URI http://asc.fasb.org/extlink&oid=121370832&loc=SL117420844-207641 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 853 -SubTopic 10 -Section 65 -Paragraph 2 -Subparagraph (e)(2) -URI http://asc.fasb.org/extlink&oid=109199533&loc=SL109199563-203033 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 65 -Paragraph 4 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=109261464&loc=SL109261606-128450 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 405 -SubTopic 20 -Section 65 -Paragraph 1 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=77997009&loc=SL77997016-210199 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 105 -SubTopic 10 -Section 65 -Paragraph 4 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=117337699&loc=SL117340306-165695 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 65 -Paragraph 15 -Subparagraph (f)(2) -URI http://asc.fasb.org/extlink&oid=121322162&loc=SL121327923-165333 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 65 -Paragraph 1 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=113356391&loc=SL49131195-203048 Reference 14: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 105 -SubTopic 10 -Section 65 -Paragraph 4 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=117337699&loc=SL117340306-165695 Reference 15: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=121370832&loc=SL117420844-207641 Reference 16: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 20 -Section 65 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121483254&loc=SL120254523-199619 Reference 17: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 10 -Section 65 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121329987&loc=SL120154346-209984 Reference 18: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 10 -Section 65 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=121329987&loc=SL77916155-209984 Reference 19: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 10 -Section 65 -Paragraph 3 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=121329987&loc=SL119206272-209984 Reference 20: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 65 -Paragraph 15 -Subparagraph (f)(1) -URI http://asc.fasb.org/extlink&oid=121322162&loc=SL121327923-165333 Reference 21: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 65 -Paragraph 1 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=113356391&loc=SL49131195-203048 Reference 22: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 10 -Section 65 -Paragraph 3 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=121329987&loc=SL119206272-209984 Reference 23: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 853 -SubTopic 10 -Section 65 -Paragraph 2 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=109199533&loc=SL109199563-203033 Reference 24: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 65 -Paragraph 15 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=121322162&loc=SL121327923-165333 Reference 25: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 65 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=98513396&loc=SL94080479-196980 Reference 26: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 958 -SubTopic 10 -Section 65 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=120520240&loc=SL117035239-210619 Reference 27: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 65 -Paragraph 8 -Subparagraph (d)(3) + Details
Name: | us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateTransitionOptionElectedExtensibleList
Namespace Prefix: | us-gaap_
Data Type: | srt-types:extensibleListItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of revenue recognized from performance obligation satisfied or partially satisfied in previous reporting periods. Includes, but is not limited to, change in transaction price. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 12A -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL108322424-203045 + Details
Name: | us-gaap_ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 + Details
Name: | us-gaap_DebtInstrumentFaceAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201613Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201815Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=kalu_SeniorNotesDueTwoThousandAndTwentyFiveMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |