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Income Taxes - Reconciliation of Provision for Income Taxes with Federal Statutory Income Tax Rate (Detail) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Income Tax Disclosure [Abstract] |  |  |
Federal statutory rate | $ 248.9 | $ 278.7 | $ 204.8
State income taxes - net of federal benefit | 49.7 | 32.9 | 30.7
Differences related to non U.S. operations | (20.6) | (31.9) | (8.7)
Alternative energy and other tax credits | (7.9) | (6.9) | (199.0)
Other permanent differences | 27.6 | 22.5 | (3.5)
Stock-based compensation | (76.1) | (59.3) | (40.0)
Changes in unrecognized tax benefits | 11.9 | 4.0 | 0.8
Change in valuation allowance | 3.9 | 15.5 | 26.4
Change in U.S. and U.K. tax rates | (18.3) | (44.5) | 8.6
Total provision for income taxes | $ 219.1 | $ 211.0 | $ 20.1
Federal statutory rate, % of Pretax Earnings | 21.00% | 21.00% | 21.00%
State income taxes-net of Federal benefit, % of Pretax Earnings | 4.20% | 2.50% | 3.20%
Differences related to non U.S. operations, % of Pretax Earnings | (1.70%) | (2.40%) | (0.90%)
Alternative energy and other tax credits, % of Pretax Earnings | (0.70%) | (0.50%) | (20.40%)
Other permanent differences, % of Pretax Earnings | 2.30% | 1.70% | (0.40%)
Stock-based compensation | (6.40%) | (4.50%) | (4.10%)
Changes in unrecognized tax benefits, % of Pretax Earnings | 1.00% | 0.30% | 0.10%
Change in valuation allowance, % of Pretax Earnings | 0.30% | 1.20% | 2.70%
Change in U.S. and U.K. tax rates | (1.50%) | (3.40%) | 0.90%
Total provision for income taxes, % of Pretax Earnings | 18.50% | 15.90% | 2.10%

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