v3.25.0.1
Income Taxes (Tables)
 12 Months Ended
Dec. 31, 2024
Income Tax Disclosure [Abstract]  
Schedule of components of the provision for income taxes
The components of the provision for income taxes for the years ended December 31 follow:
202420232022
Current:
Federal
$207 $281 $72 
State
120 109 82 
Deferred:
Federal
55 72 164 
State
32 29 17 
Uncertain tax positions and interest and other(26)(31)9 
Provision for income taxes$388 $460 $344 
Schedule of reconciliations of the statutory federal income tax rate to our effective tax rate
The reconciliations of the statutory federal income tax rate to our effective tax rate for the years ended December 31 follow:
202420232022
Federal statutory rate21.0 %21.0 %21.0 %
State income taxes, net of federal benefit4.8 4.4 4.6 
Non-deductible expenses0.8 1.2 1.1 
Uncertain tax position taxes and interest(0.3)(0.8)0.2 
Investment tax credits(9.9)(4.0)(7.6)
Other, net(0.4)(0.8)(0.5)
Effective income tax rate16.0 %21.0 %18.8 %
Schedule of components of the net deferred income tax asset and liability
The components of the net deferred income tax asset and liability as of December 31 follow:
20242023
Deferred tax liabilities relating to:
Differences between book and tax basis of property and equipment
$(1,258)$(1,229)
Difference between book and tax basis of intangible assets
(637)(583)
Operating right-of-use lease assets
(57)(59)
Basis difference due to redemption of partnership interests
(82)(82)
Total deferred tax liabilities
$(2,034)$(1,953)
Deferred tax assets relating to:
Environmental reserves
$218 $236 
Accruals not currently deductible
105 105 
Net operating loss carryforwards
61 75 
Difference between book and tax basis of other assets
48 14 
Operating right-of-use lease liabilities
59 60 
Other
15 17 
Total deferred tax assets
506 507 
Valuation allowance
(51)(49)
Net deferred tax asset
455 458 
Net overall deferred tax liability$(1,579)$(1,495)
Schedule of changes in the deferred tax valuation allowance
Changes in the deferred tax valuation allowance for the years ended December 31 follow:
202420232022
Valuation allowance, beginning of year$49 $44 $44 
Additions charged to provision for income taxes6 3 2 
Deferred tax assets realized or written-off— — (6)
Other, net(4)2 4 
Valuation allowance, end of year$51 $49 $44 
Schedule of activity in our gross unrecognized tax benefits
The following table summarizes the activity in our gross unrecognized tax benefits for the years ended December 31:
202420232022
Balance at beginning of year$42 $111 $102 
Additions for tax positions of current year— 1 7 
Additions for tax positions of prior years1 3 2 
Reductions for tax positions of prior years(5)(7)— 
Reductions for tax positions resulting from lapse of statute of limitations(1)— — 
Settlements(9)(66)— 
Balance at end of year$28 $42 $111