v3.22.4

Contingencies and Commitments​ (Details) |  |  |  |  |  |  |  |  |  | 1 Months Ended | 3 Months Ended | 8 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Mar. 31, 2022 claimant | Mar. 29, 2022 defendant claimant | Dec. 23, 2020 claimant defendant | Jun. 26, 2020 claimant | Jun. 12, 2020 police_officer claimant firefighter | Jun. 11, 2020 firefighter | Mar. 17, 2020 segment | Jun. 06, 2019 plaintiff | Sep. 15, 2017 executive | Jul. 31, 2022 USD ($) | Dec. 31, 2022 USD ($) | Feb. 23, 2021 firefighter | Feb. 23, 2021 firefighter | Dec. 31, 2022 USD ($) claimant firefighter yr police_officer | Dec. 31, 2021 USD ($) police_officer | Dec. 31, 2020 USD ($) | Feb. 20, 2023 USD ($) | Jan. 01, 2023 USD ($) | Feb. 05, 2020 USD ($) | Aug. 31, 2012 USD ($)
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Environmental remediation |  |  |  |  |  |  |  |  |  |  | $ 85,000,000 |  |  | $ 85,000,000 | $ 64,000,000 |  |  |  |  |
Environmental remediation, current |  |  |  |  |  |  |  |  |  |  | 40,000,000 |  |  | 40,000,000 | 15,000,000 |  |  |  |  |
Remediation reserve decrease |  |  |  |  |  |  |  |  |  |  |  |  |  | 33,000,000 | (5,000,000) | $ (2,000,000) |  |  |  |
Accrual for Environmental Loss Contingencies, Revision in Estimates |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5,000,000 |  |  |  |
Environmental remediation, additions |  |  |  |  |  |  |  |  |  |  |  |  |  | 6,000,000 |  |  |  |  |  |
Environmental remediation, payments |  |  |  |  |  |  |  |  |  |  |  |  |  | 11,000,000 | 84,000,000 | 82,000,000 |  |  |  |
Environmental remediation, increase for obligations transferred in connection with Separation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 13,000,000 |  |  |  |
Environmental remediation, decrease for other items |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000,000 | 3,000,000 | 3,000,000 |  |  |  |
Long-Term Purchase Commitment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Purchase commitments due in 2023 |  |  |  |  |  |  |  |  |  |  | 909,000,000 |  |  | 909,000,000 |  |  |  |  |  |
Purchase commitments due in 2024 |  |  |  |  |  |  |  |  |  |  | 106,000,000 |  |  | 106,000,000 |  |  |  |  |  |
Purchase commitments due in 2025 |  |  |  |  |  |  |  |  |  |  | 19,000,000 |  |  | 19,000,000 |  |  |  |  |  |
Purchase commitments due in 2026 |  |  |  |  |  |  |  |  |  |  | 15,000,000 |  |  | 15,000,000 |  |  |  |  |  |
Purchase commitments due in 2027 |  |  |  |  |  |  |  |  |  |  | 13,000,000 |  |  | 13,000,000 |  |  |  |  |  |
Purchase commitments due thereafter |  |  |  |  |  |  |  |  |  |  | 24,000,000 |  |  | 24,000,000 |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  |  |  |  |  | 700,000,000 |  |  | 700,000,000 | $ 700,000,000 |  |  |  | $ 1,200,000,000 |
Obligations to Perform Operations, Maintenance, and Monitoring at Environmental Remediation Sites |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accrual for Environmental Loss Contingencies, Revision in Estimates |  |  |  |  |  |  |  |  |  |  | (9,000,000) |  |  |  |  |  |  |  |  |
Behrens v. Arconic |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | plaintiff |  |  |  |  |  |  |  | 247 |  |  |  |  |  |  |  |  |  |  |  |
Sullivan v. Arconic |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of former executives | executive |  |  |  |  |  |  |  |  | 3 |  |  |  |  |  |  |  |  |  |  |
Aluminum Rolling Mill in Brazil |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Environmental remediation, additions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000,000 |  |  |  |
Aluminum Supply Contract | Subsequent events |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-Term Purchase Commitment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Purchase commitments due in 2023 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 375,000,000 |  |
Purchase commitments due in 2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 195,000,000 |  |
Purchase commitments due in 2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 195,000,000 |  |
Unrecorded Unconditional Purchase Obligation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,580,000,000 | $ 765,000,000 |  |
Grenfell Tower Fire |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingency Accrual, Provision |  |  |  |  |  |  |  |  |  |  |  |  |  | 61,000,000 |  |  |  |  |  |
Loss Contingency, Receivable, Additions |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 53,000,000 |  |  |  |  |  |
Grenfell Tower Fire | Grenfell Tower Fire, Survivors and Estates of Decedents |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of defendants | defendant |  | 21 | 23 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Grenfell Tower Fire | Survivors and Estates of Decedents, Represented by Birnberg Peirce Ltd |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | claimant |  |  | 113 |  | 4 |  |  |  |  |  |  |  |  | 106 |  |  |  |  |  |
Grenfell Tower Fire | Survivors and Estates of Decedents, Represented by Howe & Co Solicitors |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | claimant |  |  |  |  | 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Grenfell Tower Fire | Survivors and Estates of Decedents, Represented by Russell-Cooke LLP |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | claimant |  | 1 | 33 | 3 |  |  |  |  |  |  |  |  |  | 34 |  |  |  |  |  |
Grenfell Tower Fire | Survivors and Estates of Decedents, Represented by Deighton Pierce Glynn |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | claimant |  |  | 7 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Grenfell Tower Fire | GreSurvivors and Estates of Decedents, Represented by SMQ Legal Services |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | claimant |  |  | 6 |  |  |  |  |  |  |  |  |  |  | 7 |  |  |  |  |  |
Grenfell Tower Fire | Survivors and Estates of Decedents, Represented by Scott Moncrieff |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | claimant |  |  | 3 |  |  |  |  |  |  |  |  |  |  | 4 |  |  |  |  |  |
Grenfell Tower Fire | Survivors and Estates of Decedents, Represented by Saunders Law |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | claimant |  |  | 27 |  |  |  |  |  |  |  |  |  |  | 31 |  |  |  |  |  |
Grenfell Tower Fire | Survivors and Estates of Decedents, Represented by Imran Khan & Partners |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | claimant |  |  | 40 |  |  |  |  |  |  |  |  |  |  | 47 |  |  |  |  |  |
Grenfell Tower Fire | Survivors and Estates of Decedents, Represented by Howe & Co |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | claimant |  |  | 61 |  |  |  |  |  |  |  |  |  |  | 57 |  |  |  |  |  |
Grenfell Tower Fire | Survivors and Estates of Decedents, Represented by Hodge Jones and Allen Solicitor |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | claimant |  | 5 | 119 |  |  |  |  |  |  |  |  |  |  | 4 |  |  |  |  |  |
Grenfell Tower Fire | Survivors and Estates of Decedents, Represented by Hickman & Rose |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | claimant |  |  | 19 |  |  |  |  |  |  |  |  |  |  | 23 |  |  |  |  |  |
Grenfell Tower Fire | Survivors and Estates of Decedents, Represented by Duncan Lewis Solicitors |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | claimant |  |  | 10 |  |  |  |  |  |  |  |  |  |  | 12 |  |  |  |  |  |
Grenfell Tower Fire | Survivors and Estates of Decedents, Represented by Bindmans LLP |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | claimant | 5 |  | 346 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Grenfell Tower Fire | Survivors and Estates of Decedents, Represented by Bhatt Murphy Ltd |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | claimant |  |  | 76 |  |  |  |  |  |  |  |  |  |  | 80 |  |  |  |  |  |
Grenfell Tower Fire | Emergency Responders, Represented by Thompsons Solicitors |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | firefighter |  |  |  |  |  | 98 |  |  |  |  |  |  |  | 80 |  |  |  |  |  |
Number of additional plaintiffs added to suit | firefighter |  |  |  |  |  |  |  |  |  |  |  | 10 |  | 7 |  |  |  |  |  |
Grenfell Tower Fire | Emergency Responders, Represented by Penningtons Manches Cooper LLP |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | police_officer |  |  |  |  | 27 |  |  |  |  |  |  |  |  | 33 | 36 |  |  |  |  |
Grenfell Tower Fire | Emergency Responders, Represented by Pattinson and Brewer |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | firefighter |  |  |  |  | 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants withdrawn from suit | firefighter |  |  |  |  |  |  |  |  |  |  |  |  | 1 |  |  |  |  |  |  |
Grenfell Tower Fire | Grenfell Tower Fire, Survivors And Estates Of Decedents, Represented By Slater & Gordon |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of claimants/plaintiffs | claimant |  |  | 26 |  |  |  |  |  |  |  |  |  |  | 27 |  |  |  |  |  |
Non-Compliance with Russian Federal Law No. 57-FZ | Federal Antimonopoly Services of the Russian Federation Litigation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingency, Number Of Subsidiaries | segment |  |  |  |  |  |  | 2 |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantee Obligations |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor obligations, carrying value |  |  |  |  |  |  |  |  |  |  | 2,000,000 |  |  | $ 2,000,000 |  |  |  |  |  |
Guarantee Obligations | Howmet Aerospace | Arconic Corporation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor obligations, carrying value |  |  |  |  |  |  |  |  |  |  | 0 |  |  | 0 |  |  |  |  |  |
Guarantee Obligations | Alcoa Corporation | Arconic Corporation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor obligations, carrying value |  |  |  |  |  |  |  |  |  |  | 8,000,000 |  |  | 8,000,000 |  |  |  |  |  |
Standby Letters of Credit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total amount committed under letters of credit |  |  |  |  |  |  |  |  |  |  | 11,000,000 |  |  | 11,000,000 |  |  |  |  |  |
Standby Letters of Credit | Howmet Aerospace | Arconic Corporation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total amount committed under letters of credit |  |  |  |  |  |  |  |  |  |  | 27,000,000 |  |  | 27,000,000 |  |  |  |  |  |
Standby Letters of Credit | Alcoa Corporation | Arconic Corporation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total amount committed under letters of credit |  |  |  |  |  |  |  |  |  |  | 0 |  |  | 0 |  |  |  |  |  |
Surety Bonds |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total amount committed under surety bonds |  |  |  |  |  |  |  |  |  |  | 48,000,000 |  |  | 48,000,000 |  |  |  |  |  |
Surety Bonds | Howmet Aerospace | Arconic Corporation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total amount committed under surety bonds |  |  |  |  |  |  |  |  |  |  | 4,000,000 |  |  | 4,000,000 |  |  |  |  |  |
Surety Bonds | Alcoa Corporation | Arconic Corporation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total amount committed under surety bonds |  |  |  |  |  |  |  |  |  |  | 2,000,000 |  |  | 2,000,000 |  |  |  |  |  |
Active Remediation Systems and/or Monitoring and Inspection Programs at Several Sites |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Environmental remediation, additions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,000,000 |  |  |  |
Environmental remediation, decrease for other items |  |  |  |  |  |  |  |  |  |  |  |  |  | 14,000,000 | $ 4,000,000 |  |  |  |  |
Massena West, NY |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Environmental remediation |  |  |  |  |  |  |  |  |  |  | 38,000,000 |  |  | 38,000,000 | 30,000,000 |  |  |  |  |
Accrual for Environmental Loss Contingencies, Revision in Estimates |  |  |  |  |  |  |  |  |  |  |  |  |  | (11,000,000) | (11,000,000) |  |  |  |  |
Massena West, NY | Legal Matters, Other |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accrual for Environmental Loss Contingencies, Revision in Estimates |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ (2,000,000) |  |  |  |  |
Massena West, NY | Environmental Issue [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Environmental remediation, additions |  |  |  |  |  |  |  |  |  |  |  |  |  | 13,000,000 |  |  |  |  |  |
Massena West, NY | Environmental Issue [Member] | Scenario, Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accrual for Environmental Loss Contingencies, Revision in Estimates |  |  |  |  |  |  |  |  |  | $ (22,000,000) |  |  |  |  |  |  |  |  |  |
Lafayette, Indiana |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Remediation reserve decrease |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5,000,000 |  |  |  |  |  |
Accrual for Environmental Loss Contingencies, Years for Completion | yr |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 |  |  |  |  |  |
Fusina, Italy |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Remediation reserve decrease |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,000,000 |  |  |  |  |  |
Environmental remediation, payments |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000,000 |  |  |  |  |  |
Davenport, IA |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Environmental remediation, additions |  |  |  |  |  |  |  |  |  |  |  |  |  | 500,000 |  |  |  |  |  |
Davenport, IA | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated Future Capital Expenditures |  |  |  |  |  |  |  |  |  |  | 25,000,000 |  |  | 25,000,000 |  |  |  |  |  |
Davenport, IA | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated Future Capital Expenditures |  |  |  |  |  |  |  |  |  |  | $ 30,000,000 |  |  | $ 30,000,000 |  |  |  |  |  |
Midwestern Disaster Area Revenue Bonds Series 2012 | Bonds |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 250,000,000

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