XML 200 R97.htm IDEA: XBRL DOCUMENT
v3.24.0.1

EMPLOYEE BENEFIT PLANS - Fair Value of Plan Assets (Details) - Defined benefit pension plan - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | --- | ---
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | $ 97,252 | $ 92,129 | $ 113,976
Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 75,912 | 5,422 |
Level 1 |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 75,883 | 5,422 |
Level 2 |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 29 |  |
Consumer discretionary | Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 2,605 |  |
Consumer discretionary | Level 1 |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 2,605 |  |
Consumer durables | Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 2,088 |  |
Consumer durables | Level 1 |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 2,088 |  |
Energy | Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 952 |  |
Energy | Level 1 |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 952 |  |
Financials | Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 4,852 |  |
Financials | Level 1 |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 4,852 |  |
Health Care | Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 4,296 |  |
Health Care | Level 1 |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 4,296 |  |
Industrials & materials | Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 4,507 |  |
Industrials & materials | Level 1 |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 4,507 |  |
Information technology & communication | Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 8,102 |  |
Information technology & communication | Level 1 |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 8,102 |  |
Preferred stocks non-convertible | Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 37 |  |
Preferred stocks non-convertible | Level 1 |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 37 |  |
Mid-cap stock funds | Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 11,847 |  |
Mid-cap stock funds | Level 1 |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 11,847 |  |
Small-cap stock funds | Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 4,007 |  |
Small-cap stock funds | Level 1 |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 4,007 |  |
International stock funds | Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 7,849 |  |
International stock funds | Level 1 |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 7,849 |  |
Large-cap blend - S&P 500 index | Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 18,044 |  |
Large-cap blend - S&P 500 index | Level 1 |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 18,044 |  |
International - Developed markets | Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 3,138 |  |
International - Developed markets | Level 1 |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 3,138 |  |
International - Emerging markets | Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 1,894 |  |
International - Emerging markets | Level 1 |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 1,894 |  |
Accrued income | Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 29 |  |
Accrued income | Level 2 |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 29 |  |
Cash And Cash Equivalents | Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 1,665 | 5,422 |
Cash And Cash Equivalents | Level 1 |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 1,665 | 5,422 |
Equities - United States | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets |  | 36,259 |
Equities - United States futures | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets |  | (697) |
Equities - International developed markets | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets |  | 14,214 |
Equities - International developed markets futures | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets |  | (1,693) |
Equities - International emerging markets | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets |  | 782 |
Equities - International emerging markets futures | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets |  | 3,289 |
Fixed income - Investment grade | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | $ 21,340 | 13,856 |
Fixed income - High yield | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets |  | 156 |
Fixed income - Futures | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets |  | 8,590 |
Alternatives | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets |  | $ 11,951 |

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_DefinedBenefitPlanDisclosureLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(02) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
Name: | us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_PensionPlansDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel12And3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_EquitySecuritiesConsumerDiscretionaryMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_DefinedBenefitPlanEquitySecuritiesConsumerDurablesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_DefinedBenefitPlanEquitySecuritiesEnergyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_DefinedBenefitPlanEquitySecuritiesFinancialsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_DefinedBenefitPlanEquitySecuritiesHealthCareMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_DefinedBenefitPlanEquitySecuritiesIndustrialMaterialsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_DefinedBenefitPlanEquitySecuritiesInformationTechnologyCommunicationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_PreferredStockNonConvertibleFixedIncomeInvestmentsIndividualSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_DefinedBenefitPlanEquitySecuritiesMidCapMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_DefinedBenefitPlanEquitySecuritiesSmallCapMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_DefinedBenefitPlanEquitySecuritiesInternationalStockFundsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_DefinedBenefitPlansEquityInvestmentsExchangeTradedFundsLargeCapBlendSP500IndexMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_DefinedBenefitPlansEquityInvestmentsInternationalDevelopedMarketsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_DefinedBenefitPlansEquityInvestmentsInternationalEmergingMarketsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_DefinedBenefitPlanAccruedIncomeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_DefinedBenefitPlanCashAndCashEquivalentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_DefinedBenefitPlanEquitySecuritiesUnitedStatesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueMeasuredAtNetAssetValuePerShareMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_DefinedBenefitPlanEquitySecuritiesUnitedStatesFuturesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_EquitySecuritiesInternationallyDevelopedMarketsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_EquitySecuritiesInternationallyDevelopmentMarketsFuturesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_EquitySecuritiesInternationallyEmergingMarketsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_EquitySecuritiesInternationallyEmergingMarketsFuturesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_FixedIncomeSecuritiesInvestmentGradeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_FixedIncomeSecuritiesHighYieldMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=arlp_FixedIncomeSecuritiesFuturesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_MiscellaneousInvestmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |