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Income Taxes Effective tax rate (Details 2) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Income Tax [Line Items] |  |  |  |  |
Increase (Decrease) in Royalties Payable |  |  |  | $ 10.4 |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount |  |  | $ 945.8 | 553.5 | $ (18.7)
Valuation allowance | $ 1,530.5 |  | 1,530.5 | 584.1 |
Alternative minimum tax credit carryforwards | 100.4 |  | 100.4 | 8.6 |
Undistributed earnings of non-U.S. subsidiaries | 15.0 |  | 15.0 | 15.0 |
Effective Income Tax Rate Reconciliation, Other Reconciling Items, Amount |  |  | 0.7 | $ (15.1) | (54.2)
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount |  |  |  |  | $ 23.3
Undistributed earnings withholding taxes |  |  | $ 15.0 |  |
Computed tax at the U.S. federal statutory rate |  |  | 21.00% | 35.00% | 35.00%
Deferred Income Tax Expense (Benefit) |  |  | $ (96.4) | $ 616.6 | $ (111.5)
Refund of Future Alternative Minimum Tax Credits |  |  | (8.6) |  |
The components of earnings from consolidated companies before income taxes, and the effects of significant adjustments to tax computed at the federal statutory rate, were as follows: |  |  |  |  |
United States earnings (loss) |  |  | 322.7 | (82.5) | (96.4)
Non-U.S. earnings |  |  | 228.8 | 456.5 | 338.8
Earnings from consolidated companies before income taxes |  |  | $ 551.5 | $ 374.0 | $ 242.4
Effective Income Tax Rate Continuing Operations Tax Rate Reconciliation |  |  |  |  |
State and local income taxes, net of federal income tax benefit |  |  | 2.00% | (0.10%) | (6.10%)
Percentage depletion in excess of basis |  |  | (6.70%) | (13.20%) | (34.40%)
Impact of non-U.S. earnings |  |  | 11.80% | (46.90%) | (4.00%)
Change in valuation allowance |  |  | (15.20%) | 148.80% | 7.70%
Resolution of uncertain tax positions |  |  | (0.40%) | 0.00% | (34.90%)
Share-based excess cost/(benefits) |  |  | 0.70% | 2.00% | 2.20%
Other items (none in excess of 5% of computed tax) |  |  | 0.80% | 6.70% | 3.90%
Effective tax rate |  |  | 14.00% | 132.30% | (30.60%)
Effective Income Tax Rate Reconciliation, Amounts |  |  |  |  |
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount |  |  | $ 1.0 | $ 6.1 |
Effective income tax rate reconciliation, resolution of Advanced Pricing Agreement, amount |  |  |  |  | $ (85.8)
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Amount |  |  |  | 7.5 | $ 8.3
Foreign Tax Credit Carryforward [Member] |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount |  |  | (30.6) |  |
United States |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |
Deferred Income Tax Expense (Benefit) |  |  |  | 14.9 |
Peru |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount |  |  | 6.7 |  |
United States Tax Cuts and Jobs Act Law [Member] |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount |  |  | 30.7 |  |
Valuation allowance | 440.3 |  | 440.3 | 546.1 |
Alternative minimum tax credit carryforwards | 121.5 |  | 121.5 |  |
Estimated impacts on deferred tax and tax expenses |  |  |  | 457.5 |
Undistributed earnings of non-U.S. subsidiaries |  |  |  | 202.6 |
Sequestration Rules, refundable alternative minimum tax |  |  | 8.6 |  |
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount | 9.0 |  | 12.2 | 107.7 |
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount |  |  | $ 2.3 |  |
Computed tax at the U.S. federal statutory rate |  |  | 21.00% |  |
Foreign Tax Authority [Member] |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount |  |  | $ 11.7 |  |
Anticipatory Foreign Tax Credit Carryforward [Member] | United States Tax Cuts and Jobs Act Law [Member] |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |
Valuation allowance | 361.6 |  | 361.6 | 440.3 |
Foreign Tax Credit Carryforward [Member] |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |
Tax Credit Carryforward, Amount | 493.5 |  | 493.5 |  |
Foreign Tax Credit Carryforward [Member] | United States Tax Cuts and Jobs Act Law [Member] |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount |  |  | 30.6 |  |
Valuation allowance | 156.8 |  | 156.8 | $ 105.8 |
Alternative Minimum Tax Credit Carryforward [Member] |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |
Tax Credit Carryforward, Amount | 76.5 |  | 76.5 |  |
Alternative Minimum Tax Credit Carryforward [Member] | United States Tax Cuts and Jobs Act Law [Member] |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |
Tax Credit Carryforward, Amount | 100.4 |  | 100.4 |  |
Estimate | United States Tax Cuts and Jobs Act Law [Member] |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount |  | $ 21.2 |  |  |
Tax Year 2028 Or Earlier [Member] | Foreign Tax Credit Carryforward [Member] |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |
Tax Credit Carryforward, Amount | $ 221.6 |  | 221.6 |  |
Vale Fertilizantes S.A. [Member] |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount |  |  | $ 956.2 |  |

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