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Segments Of Business | 12 Months Ended
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Dec. 31, 2024
Segment Reporting Information [Line Items] |
Segments Of Business | SEGMENTS OF BUSINESS Alliant Energy - Alliant Energy’s reportable segments as of December 31, 2024 are: •IPL - is a utility primarily serving electric and natural gas customers in Iowa, and is its own reportable segment as shown in the tables below. •WPL - is a utility serving electric and natural gas customers in Wisconsin, and is its own reportable segment as shown in the tables below. Other, which is not a reportable segment of Alliant Energy, includes the operations of AEF and its subsidiaries, Corporate Services, the Alliant Energy parent company, and any Alliant Energy parent company consolidating adjustments. AEF is comprised of Alliant Energy’s interest in ATC Holdings, Travero, a non-utility wind farm, corporate venture investments, the Sheboygan Falls Energy Facility and other non-utility holdings. The “Other” columns are included in the tables below to reconcile to consolidated amounts. Prior to December 31, 2024, reportable segments for Alliant Energy’s, IPL’s, and WPL’s utility business were electric operations, gas operations, and other. In the fourth quarter of 2024, Alliant Energy, IPL and WPL adopted the Financial Accounting Standards Board’s accounting standard for improvements to reportable segment disclosures. Previously reported information for prior periods has been recast to conform with the current period presentation. Alliant Energy’s chief operating decision maker (CODM) is its President and CEO, and IPL’s and WPL’s CODM is their CEO. The CODM uses net income generated from IPL’s and WPL’s operations to assess segment performance, make operating decisions, and allocate resources. Alliant Energy’s administrative support services are directly charged to the applicable segment where practicable. In all other cases, administrative support services are allocated to the applicable segment based on services agreements. There was no single customer whose revenues were 10% or more of Alliant Energy’s, IPL’s and WPL’s respective consolidated revenues. All of Alliant Energy’s, IPL’s and WPL’s operations and assets are located in the U.S. Certain financial information relating to Alliant Energy’s, IPL’s and WPL’s reportable segments, which represents the services provided to their customers, and reconciliation to consolidated amounts, was as follows (in millions):
| Utility |  |  |  |
|  |  |  |  | Total |  |  |  | Alliant
|  |  |  |  | Reportable |  |  |  | Energy
2024 | IPL |  | WPL |  | Segments |  | Other |  | Consolidated
Electric utility revenues | $1,747 |  |  | $1,625 |  |  | $3,372 |  |  | N/A |  | $3,372
Gas utility revenues | 250 |  |  | 215 |  |  | 465 |  |  | N/A |  | 465
Other revenues | 49 |  |  | 5 |  |  | 54 |  |  | $90 |  | 144
Total revenues | 2,046 |  |  | 1,845 |  |  | 3,891 |  |  | 90 |  | 3,981
Electric production fuel and purchased power expense | 269 |  |  | 359 |  |  | 628 |  |  | N/A |  | 628
Electric transmission service expense | 417 |  |  | 196 |  |  | 613 |  |  | N/A |  | 613
Cost of gas sold expense | 123 |  |  | 101 |  |  | 224 |  |  | N/A |  | 224
Asset valuation charge for IPL’s Lansing Generation Station | 60 |  |  | — |  |  | 60 |  |  | N/A |  | 60
Other operation and maintenance expense | 358 |  |  | 279 |  |  | 637 |  |  | 39 |  | 676
Other segment items: |  |  |  |  |  |  |  |  |
Depreciation and amortization expense | 404 |  |  | 357 |  |  | 761 |  |  | 11 |  | 772
Interest expense | 177 |  | 165 |  | 342 |  | 107 |  | 449
Equity income from unconsolidated investments, net | — |  |  | (2) |  |  | (2) |  |  | (59) |  | (61)
Income tax expense (benefit) | (129) |  |  | 11 |  | (118) |  |  | 4 |  | (114)
Other (a) | 5 |  |  | 34 |  | 39 |  |  | 5 |  | 44
Net income (loss) | 362 |  | 345 |  | 707 |  | (17) |  | 690
Total assets | 11,407 |  |  | 10,106 |  |  | 21,513 |  |  | 1,201 |  | 22,714
Investments in equity method subsidiaries | 5 |  |  | 17 |  |  | 22 |  |  | 601 |  | 623
Construction and acquisition expenditures | 1,224 |  |  | 828 |  |  | 2,052 |  |  | 197 |  | 2,249
| Utility |  |  |  |
|  |  |  |  | Total |  |  |  | Alliant
|  |  |  |  | Reportable |  |  |  | Energy
2023 (amounts may not foot due to rounding) | IPL |  | WPL |  | Segments |  | Other |  | Consolidated
Electric utility revenues | $1,761 |  |  | $1,584 |  |  | $3,345 |  |  | N/A |  | $3,345
Gas utility revenues | 300 |  |  | 240 |  |  | 540 |  |  | N/A |  | 540
Other revenues | 49 |  |  | 3 |  |  | 52 |  |  | $90 |  | 142
Total revenues | 2,110 |  |  | 1,827 |  |  | 3,937 |  |  | 90 |  | 4,027
Electric production fuel and purchased power expense | 282 |  |  | 455 |  |  | 737 |  |  | N/A |  | 736
Electric transmission service expense | 420 |  |  | 163 |  |  | 583 |  |  | N/A |  | 583
Cost of gas sold expense | 166 |  |  | 134 |  |  | 300 |  |  | N/A |  | 299
Other operation and maintenance expense | 353 |  |  | 271 |  |  | 624 |  |  | 51 |  | 675
Other segment items: |  |  |  |  |  |  |  |  |
Depreciation and amortization expense | 388 |  |  | 280 |  |  | 668 |  |  | 8 |  | 676
Interest expense | 155 |  |  | 149 |  |  | 304 |  |  | 90 |  | 394
Equity income from unconsolidated investments, net | — |  |  | (3) |  |  | (3) |  |  | (58) |  | (61)
Income tax expense (benefit) | (58) |  |  | 60 |  |  | 2 |  |  | 2 |  | 4
Other (a) | 38 |  |  | (27) |  |  | 11 |  |  | 5 |  | 18
Net income (loss) | 366 |  |  | 345 |  |  | 711 |  |  | (8) |  | 703
Total assets | 10,489 |  |  | 9,634 |  |  | 20,123 |  |  | 1,114 |  | 21,237
Investments in equity method subsidiaries | 5 |  |  | 16 |  |  | 21 |  |  | 564 |  | 585
Construction and acquisition expenditures | 712 |  |  | 1,019 |  |  | 1,731 |  |  | 123 |  | 1,854
| Utility |  |  |  |
|  |  |  |  | Total |  |  |  | Alliant
|  |  |  |  | Reportable |  |  |  | Energy
2022 | IPL |  | WPL |  | Segments |  | Other |  | Consolidated
Electric utility revenues | $1,859 |  |  | $1,562 |  |  | $3,421 |  |  | N/A |  | $3,421
Gas utility revenues | 351 |  |  | 291 |  |  | 642 |  |  | N/A |  | 642
Other revenues | 46 |  |  | 3 |  |  | 49 |  |  | $93 |  | 142
Total revenues | 2,256 |  |  | 1,856 |  |  | 4,112 |  |  | 93 |  | 4,205
Electric production fuel and purchased power expense | 383 |  |  | 447 |  |  | 830 |  |  | N/A |  | 830
Electric transmission service expense | 407 |  |  | 166 |  |  | 573 |  |  | N/A |  | 573
Cost of gas sold expense | 206 |  |  | 183 |  |  | 389 |  |  | N/A |  | 389
Other operation and maintenance expense | 369 |  |  | 278 |  |  | 647 |  |  | 57 |  | 704
Other segment items: |  |  |  |  |  |  |  |  |
Depreciation and amortization expense | 381 |  |  | 283 |  |  | 664 |  |  | 7 |  | 671
Interest expense | 148 |  |  | 121 |  |  | 269 |  |  | 56 |  | 325
Equity income from unconsolidated investments, net | — |  |  | (1) |  |  | (1) |  |  | (50) |  | (51)
Income tax expense (benefit) | (50) |  |  | 66 |  |  | 16 |  |  | 6 |  | 22
Other (a) | 52 |  |  | (2) |  |  | 50 |  |  | 6 |  | 56
Net income | 360 |  |  | 315 |  |  | 675 |  |  | 11 |  | 686
Total assets | 10,075 |  |  | 8,987 |  |  | 19,062 |  |  | 1,101 |  | 20,163
Investments in equity method subsidiaries | 5 |  |  | 15 |  |  | 20 |  |  | 522 |  | 542
Construction and acquisition expenditures | 372 |  |  | 1,020 |  |  | 1,392 |  |  | 92 |  | 1,484
(a)Other segment items for each reportable segment include AFUDC, taxes other than income taxes, interest income, and other miscellaneous income and deductions.
IPL [Member] |
Segment Reporting Information [Line Items] |
Segments Of Business | SEGMENTS OF BUSINESS Alliant Energy - Alliant Energy’s reportable segments as of December 31, 2024 are: •IPL - is a utility primarily serving electric and natural gas customers in Iowa, and is its own reportable segment as shown in the tables below. •WPL - is a utility serving electric and natural gas customers in Wisconsin, and is its own reportable segment as shown in the tables below. Other, which is not a reportable segment of Alliant Energy, includes the operations of AEF and its subsidiaries, Corporate Services, the Alliant Energy parent company, and any Alliant Energy parent company consolidating adjustments. AEF is comprised of Alliant Energy’s interest in ATC Holdings, Travero, a non-utility wind farm, corporate venture investments, the Sheboygan Falls Energy Facility and other non-utility holdings. The “Other” columns are included in the tables below to reconcile to consolidated amounts. Prior to December 31, 2024, reportable segments for Alliant Energy’s, IPL’s, and WPL’s utility business were electric operations, gas operations, and other. In the fourth quarter of 2024, Alliant Energy, IPL and WPL adopted the Financial Accounting Standards Board’s accounting standard for improvements to reportable segment disclosures. Previously reported information for prior periods has been recast to conform with the current period presentation. Alliant Energy’s chief operating decision maker (CODM) is its President and CEO, and IPL’s and WPL’s CODM is their CEO. The CODM uses net income generated from IPL’s and WPL’s operations to assess segment performance, make operating decisions, and allocate resources. Alliant Energy’s administrative support services are directly charged to the applicable segment where practicable. In all other cases, administrative support services are allocated to the applicable segment based on services agreements. There was no single customer whose revenues were 10% or more of Alliant Energy’s, IPL’s and WPL’s respective consolidated revenues. All of Alliant Energy’s, IPL’s and WPL’s operations and assets are located in the U.S. Certain financial information relating to Alliant Energy’s, IPL’s and WPL’s reportable segments, which represents the services provided to their customers, and reconciliation to consolidated amounts, was as follows (in millions):
| Utility |  |  |  |
|  |  |  |  | Total |  |  |  | Alliant
|  |  |  |  | Reportable |  |  |  | Energy
2024 | IPL |  | WPL |  | Segments |  | Other |  | Consolidated
Electric utility revenues | $1,747 |  |  | $1,625 |  |  | $3,372 |  |  | N/A |  | $3,372
Gas utility revenues | 250 |  |  | 215 |  |  | 465 |  |  | N/A |  | 465
Other revenues | 49 |  |  | 5 |  |  | 54 |  |  | $90 |  | 144
Total revenues | 2,046 |  |  | 1,845 |  |  | 3,891 |  |  | 90 |  | 3,981
Electric production fuel and purchased power expense | 269 |  |  | 359 |  |  | 628 |  |  | N/A |  | 628
Electric transmission service expense | 417 |  |  | 196 |  |  | 613 |  |  | N/A |  | 613
Cost of gas sold expense | 123 |  |  | 101 |  |  | 224 |  |  | N/A |  | 224
Asset valuation charge for IPL’s Lansing Generation Station | 60 |  |  | — |  |  | 60 |  |  | N/A |  | 60
Other operation and maintenance expense | 358 |  |  | 279 |  |  | 637 |  |  | 39 |  | 676
Other segment items: |  |  |  |  |  |  |  |  |
Depreciation and amortization expense | 404 |  |  | 357 |  |  | 761 |  |  | 11 |  | 772
Interest expense | 177 |  | 165 |  | 342 |  | 107 |  | 449
Equity income from unconsolidated investments, net | — |  |  | (2) |  |  | (2) |  |  | (59) |  | (61)
Income tax expense (benefit) | (129) |  |  | 11 |  | (118) |  |  | 4 |  | (114)
Other (a) | 5 |  |  | 34 |  | 39 |  |  | 5 |  | 44
Net income (loss) | 362 |  | 345 |  | 707 |  | (17) |  | 690
Total assets | 11,407 |  |  | 10,106 |  |  | 21,513 |  |  | 1,201 |  | 22,714
Investments in equity method subsidiaries | 5 |  |  | 17 |  |  | 22 |  |  | 601 |  | 623
Construction and acquisition expenditures | 1,224 |  |  | 828 |  |  | 2,052 |  |  | 197 |  | 2,249
| Utility |  |  |  |
|  |  |  |  | Total |  |  |  | Alliant
|  |  |  |  | Reportable |  |  |  | Energy
2023 (amounts may not foot due to rounding) | IPL |  | WPL |  | Segments |  | Other |  | Consolidated
Electric utility revenues | $1,761 |  |  | $1,584 |  |  | $3,345 |  |  | N/A |  | $3,345
Gas utility revenues | 300 |  |  | 240 |  |  | 540 |  |  | N/A |  | 540
Other revenues | 49 |  |  | 3 |  |  | 52 |  |  | $90 |  | 142
Total revenues | 2,110 |  |  | 1,827 |  |  | 3,937 |  |  | 90 |  | 4,027
Electric production fuel and purchased power expense | 282 |  |  | 455 |  |  | 737 |  |  | N/A |  | 736
Electric transmission service expense | 420 |  |  | 163 |  |  | 583 |  |  | N/A |  | 583
Cost of gas sold expense | 166 |  |  | 134 |  |  | 300 |  |  | N/A |  | 299
Other operation and maintenance expense | 353 |  |  | 271 |  |  | 624 |  |  | 51 |  | 675
Other segment items: |  |  |  |  |  |  |  |  |
Depreciation and amortization expense | 388 |  |  | 280 |  |  | 668 |  |  | 8 |  | 676
Interest expense | 155 |  |  | 149 |  |  | 304 |  |  | 90 |  | 394
Equity income from unconsolidated investments, net | — |  |  | (3) |  |  | (3) |  |  | (58) |  | (61)
Income tax expense (benefit) | (58) |  |  | 60 |  |  | 2 |  |  | 2 |  | 4
Other (a) | 38 |  |  | (27) |  |  | 11 |  |  | 5 |  | 18
Net income (loss) | 366 |  |  | 345 |  |  | 711 |  |  | (8) |  | 703
Total assets | 10,489 |  |  | 9,634 |  |  | 20,123 |  |  | 1,114 |  | 21,237
Investments in equity method subsidiaries | 5 |  |  | 16 |  |  | 21 |  |  | 564 |  | 585
Construction and acquisition expenditures | 712 |  |  | 1,019 |  |  | 1,731 |  |  | 123 |  | 1,854
| Utility |  |  |  |
|  |  |  |  | Total |  |  |  | Alliant
|  |  |  |  | Reportable |  |  |  | Energy
2022 | IPL |  | WPL |  | Segments |  | Other |  | Consolidated
Electric utility revenues | $1,859 |  |  | $1,562 |  |  | $3,421 |  |  | N/A |  | $3,421
Gas utility revenues | 351 |  |  | 291 |  |  | 642 |  |  | N/A |  | 642
Other revenues | 46 |  |  | 3 |  |  | 49 |  |  | $93 |  | 142
Total revenues | 2,256 |  |  | 1,856 |  |  | 4,112 |  |  | 93 |  | 4,205
Electric production fuel and purchased power expense | 383 |  |  | 447 |  |  | 830 |  |  | N/A |  | 830
Electric transmission service expense | 407 |  |  | 166 |  |  | 573 |  |  | N/A |  | 573
Cost of gas sold expense | 206 |  |  | 183 |  |  | 389 |  |  | N/A |  | 389
Other operation and maintenance expense | 369 |  |  | 278 |  |  | 647 |  |  | 57 |  | 704
Other segment items: |  |  |  |  |  |  |  |  |
Depreciation and amortization expense | 381 |  |  | 283 |  |  | 664 |  |  | 7 |  | 671
Interest expense | 148 |  |  | 121 |  |  | 269 |  |  | 56 |  | 325
Equity income from unconsolidated investments, net | — |  |  | (1) |  |  | (1) |  |  | (50) |  | (51)
Income tax expense (benefit) | (50) |  |  | 66 |  |  | 16 |  |  | 6 |  | 22
Other (a) | 52 |  |  | (2) |  |  | 50 |  |  | 6 |  | 56
Net income | 360 |  |  | 315 |  |  | 675 |  |  | 11 |  | 686
Total assets | 10,075 |  |  | 8,987 |  |  | 19,062 |  |  | 1,101 |  | 20,163
Investments in equity method subsidiaries | 5 |  |  | 15 |  |  | 20 |  |  | 522 |  | 542
Construction and acquisition expenditures | 372 |  |  | 1,020 |  |  | 1,392 |  |  | 92 |  | 1,484
(a)Other segment items for each reportable segment include AFUDC, taxes other than income taxes, interest income, and other miscellaneous income and deductions.
WPL [Member] |
Segment Reporting Information [Line Items] |
Segments Of Business | SEGMENTS OF BUSINESS Alliant Energy - Alliant Energy’s reportable segments as of December 31, 2024 are: •IPL - is a utility primarily serving electric and natural gas customers in Iowa, and is its own reportable segment as shown in the tables below. •WPL - is a utility serving electric and natural gas customers in Wisconsin, and is its own reportable segment as shown in the tables below. Other, which is not a reportable segment of Alliant Energy, includes the operations of AEF and its subsidiaries, Corporate Services, the Alliant Energy parent company, and any Alliant Energy parent company consolidating adjustments. AEF is comprised of Alliant Energy’s interest in ATC Holdings, Travero, a non-utility wind farm, corporate venture investments, the Sheboygan Falls Energy Facility and other non-utility holdings. The “Other” columns are included in the tables below to reconcile to consolidated amounts. Prior to December 31, 2024, reportable segments for Alliant Energy’s, IPL’s, and WPL’s utility business were electric operations, gas operations, and other. In the fourth quarter of 2024, Alliant Energy, IPL and WPL adopted the Financial Accounting Standards Board’s accounting standard for improvements to reportable segment disclosures. Previously reported information for prior periods has been recast to conform with the current period presentation. Alliant Energy’s chief operating decision maker (CODM) is its President and CEO, and IPL’s and WPL’s CODM is their CEO. The CODM uses net income generated from IPL’s and WPL’s operations to assess segment performance, make operating decisions, and allocate resources. Alliant Energy’s administrative support services are directly charged to the applicable segment where practicable. In all other cases, administrative support services are allocated to the applicable segment based on services agreements. There was no single customer whose revenues were 10% or more of Alliant Energy’s, IPL’s and WPL’s respective consolidated revenues. All of Alliant Energy’s, IPL’s and WPL’s operations and assets are located in the U.S. Certain financial information relating to Alliant Energy’s, IPL’s and WPL’s reportable segments, which represents the services provided to their customers, and reconciliation to consolidated amounts, was as follows (in millions):
| Utility |  |  |  |
|  |  |  |  | Total |  |  |  | Alliant
|  |  |  |  | Reportable |  |  |  | Energy
2024 | IPL |  | WPL |  | Segments |  | Other |  | Consolidated
Electric utility revenues | $1,747 |  |  | $1,625 |  |  | $3,372 |  |  | N/A |  | $3,372
Gas utility revenues | 250 |  |  | 215 |  |  | 465 |  |  | N/A |  | 465
Other revenues | 49 |  |  | 5 |  |  | 54 |  |  | $90 |  | 144
Total revenues | 2,046 |  |  | 1,845 |  |  | 3,891 |  |  | 90 |  | 3,981
Electric production fuel and purchased power expense | 269 |  |  | 359 |  |  | 628 |  |  | N/A |  | 628
Electric transmission service expense | 417 |  |  | 196 |  |  | 613 |  |  | N/A |  | 613
Cost of gas sold expense | 123 |  |  | 101 |  |  | 224 |  |  | N/A |  | 224
Asset valuation charge for IPL’s Lansing Generation Station | 60 |  |  | — |  |  | 60 |  |  | N/A |  | 60
Other operation and maintenance expense | 358 |  |  | 279 |  |  | 637 |  |  | 39 |  | 676
Other segment items: |  |  |  |  |  |  |  |  |
Depreciation and amortization expense | 404 |  |  | 357 |  |  | 761 |  |  | 11 |  | 772
Interest expense | 177 |  | 165 |  | 342 |  | 107 |  | 449
Equity income from unconsolidated investments, net | — |  |  | (2) |  |  | (2) |  |  | (59) |  | (61)
Income tax expense (benefit) | (129) |  |  | 11 |  | (118) |  |  | 4 |  | (114)
Other (a) | 5 |  |  | 34 |  | 39 |  |  | 5 |  | 44
Net income (loss) | 362 |  | 345 |  | 707 |  | (17) |  | 690
Total assets | 11,407 |  |  | 10,106 |  |  | 21,513 |  |  | 1,201 |  | 22,714
Investments in equity method subsidiaries | 5 |  |  | 17 |  |  | 22 |  |  | 601 |  | 623
Construction and acquisition expenditures | 1,224 |  |  | 828 |  |  | 2,052 |  |  | 197 |  | 2,249
| Utility |  |  |  |
|  |  |  |  | Total |  |  |  | Alliant
|  |  |  |  | Reportable |  |  |  | Energy
2023 (amounts may not foot due to rounding) | IPL |  | WPL |  | Segments |  | Other |  | Consolidated
Electric utility revenues | $1,761 |  |  | $1,584 |  |  | $3,345 |  |  | N/A |  | $3,345
Gas utility revenues | 300 |  |  | 240 |  |  | 540 |  |  | N/A |  | 540
Other revenues | 49 |  |  | 3 |  |  | 52 |  |  | $90 |  | 142
Total revenues | 2,110 |  |  | 1,827 |  |  | 3,937 |  |  | 90 |  | 4,027
Electric production fuel and purchased power expense | 282 |  |  | 455 |  |  | 737 |  |  | N/A |  | 736
Electric transmission service expense | 420 |  |  | 163 |  |  | 583 |  |  | N/A |  | 583
Cost of gas sold expense | 166 |  |  | 134 |  |  | 300 |  |  | N/A |  | 299
Other operation and maintenance expense | 353 |  |  | 271 |  |  | 624 |  |  | 51 |  | 675
Other segment items: |  |  |  |  |  |  |  |  |
Depreciation and amortization expense | 388 |  |  | 280 |  |  | 668 |  |  | 8 |  | 676
Interest expense | 155 |  |  | 149 |  |  | 304 |  |  | 90 |  | 394
Equity income from unconsolidated investments, net | — |  |  | (3) |  |  | (3) |  |  | (58) |  | (61)
Income tax expense (benefit) | (58) |  |  | 60 |  |  | 2 |  |  | 2 |  | 4
Other (a) | 38 |  |  | (27) |  |  | 11 |  |  | 5 |  | 18
Net income (loss) | 366 |  |  | 345 |  |  | 711 |  |  | (8) |  | 703
Total assets | 10,489 |  |  | 9,634 |  |  | 20,123 |  |  | 1,114 |  | 21,237
Investments in equity method subsidiaries | 5 |  |  | 16 |  |  | 21 |  |  | 564 |  | 585
Construction and acquisition expenditures | 712 |  |  | 1,019 |  |  | 1,731 |  |  | 123 |  | 1,854
| Utility |  |  |  |
|  |  |  |  | Total |  |  |  | Alliant
|  |  |  |  | Reportable |  |  |  | Energy
2022 | IPL |  | WPL |  | Segments |  | Other |  | Consolidated
Electric utility revenues | $1,859 |  |  | $1,562 |  |  | $3,421 |  |  | N/A |  | $3,421
Gas utility revenues | 351 |  |  | 291 |  |  | 642 |  |  | N/A |  | 642
Other revenues | 46 |  |  | 3 |  |  | 49 |  |  | $93 |  | 142
Total revenues | 2,256 |  |  | 1,856 |  |  | 4,112 |  |  | 93 |  | 4,205
Electric production fuel and purchased power expense | 383 |  |  | 447 |  |  | 830 |  |  | N/A |  | 830
Electric transmission service expense | 407 |  |  | 166 |  |  | 573 |  |  | N/A |  | 573
Cost of gas sold expense | 206 |  |  | 183 |  |  | 389 |  |  | N/A |  | 389
Other operation and maintenance expense | 369 |  |  | 278 |  |  | 647 |  |  | 57 |  | 704
Other segment items: |  |  |  |  |  |  |  |  |
Depreciation and amortization expense | 381 |  |  | 283 |  |  | 664 |  |  | 7 |  | 671
Interest expense | 148 |  |  | 121 |  |  | 269 |  |  | 56 |  | 325
Equity income from unconsolidated investments, net | — |  |  | (1) |  |  | (1) |  |  | (50) |  | (51)
Income tax expense (benefit) | (50) |  |  | 66 |  |  | 16 |  |  | 6 |  | 22
Other (a) | 52 |  |  | (2) |  |  | 50 |  |  | 6 |  | 56
Net income | 360 |  |  | 315 |  |  | 675 |  |  | 11 |  | 686
Total assets | 10,075 |  |  | 8,987 |  |  | 19,062 |  |  | 1,101 |  | 20,163
Investments in equity method subsidiaries | 5 |  |  | 15 |  |  | 20 |  |  | 522 |  | 542
Construction and acquisition expenditures | 372 |  |  | 1,020 |  |  | 1,392 |  |  | 92 |  | 1,484
(a)Other segment items for each reportable segment include AFUDC, taxes other than income taxes, interest income, and other miscellaneous income and deductions.

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- Definition The entire disclosure for reporting segments including data and tables. 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