XML 132 R117.htm IDEA: XBRL DOCUMENT v3.20.4
Income Taxes - Reconciliation of Provision for Income Taxes with Federal Statutory Income Tax Rate (Detail) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Income Tax Disclosure [Abstract]      
Federal statutory rate $ 182.9 $ 131.5 $ 100.7
State income taxes - net of Federal benefit 22.2 4.4 8.5
Differences related to non U.S. operations (2.5) (10.1) (14.8)
Alternative energy and other tax credits (154.3) (196.1) (252.9)
Other permanent differences (15.7) (7.6) 0.9
U.S. repatriation tax     (1.8)
Stock-based compensation (31.4) (16.2) (15.0)
Changes in unrecognized tax benefits   0.8 (0.2)
Change in valuation allowance 6.5 7.5 (22.0)
Change in U.S. and U.K. tax rates 5.5 (3.7)  
Other (0.4) (0.2) 0.1
Total provision (benefit) for income taxes $ 12.8 $ (89.7) $ (196.5)
Federal statutory rate, % of Pretax Earnings 21.00% 21.00% 21.00%
State income taxes-net of Federal benefit, % of Pretax Earnings 2.60% 0.70% 1.80%
Differences related to non U.S. operations, % of Pretax Earnings (0.30%) (1.60%) (3.10%)
Alternative energy and other tax credits, % of Pretax Earnings (17.70%) (31.30%) (52.80%)
Other permanent differences, % of Pretax Earnings (1.80%) (1.20%) 0.20%
U.S. repatriation tax     (0.40%)
Stock-based compensation (3.60%) (2.60%) (3.10%)
Changes in unrecognized tax benefits, % of Pretax Earnings   0.10%  
Change in valuation allowance, % of Pretax Earnings 0.70% 1.20% (4.60%)
Change in U.S. and U.K. tax rates 0.60% (0.60%)  
Total provision (benefit) for income taxes, % of Pretax Earnings 1.50% (14.30%) (41.00%)