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Segments Of Business | 12 Months Ended
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Dec. 31, 2016
Segment Reporting Information [Line Items] |
Segments Of Business | SEGMENTS OF BUSINESS Alliant Energy - Alliant Energy’s principal businesses as of December 31, 2016 are:
• | Utility - includes the operations of IPL and WPL, which primarily serve retail customers in Iowa and Wisconsin. The utility business has three reportable segments: a) utility electric operations, which include Alliant Energy’s investment in ATC; b) utility gas operations; and c) utility other, which includes steam operations and the unallocated portions of the utility business. Various line items in the following tables are not allocated to the electric and gas segments for management reporting purposes, and therefore, are included only in “Total Utility.”
• | Non-regulated, Parent and Other - includes the operations of AEF and its subsidiaries, Corporate Services, the Alliant Energy parent company, and any Alliant Energy parent company consolidating adjustments. AEF’s businesses include Transportation, Non-regulated Generation and other non-regulated investments described in Note 1(a).
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. Intersegment revenues were not material to Alliant Energy’s operations and there was no single customer whose revenues were 10% or more of Alliant Energy’s consolidated revenues. All of Alliant Energy’s operations and assets are located in the U.S. Certain financial information relating to Alliant Energy’s business segments, which represent the services provided to its customers, was as follows (in millions):
| Utility |  | Non-Regulated, |  | Alliant Energy
2016 | Electric |  | Gas |  | Other |  | Total |  | Parent and Other |  | Consolidated
Operating revenues |  | $2,875.5 |  |  |  | $355.4 |  |  |  | $48.6 |  |  |  | $3,279.5 |  |  |  | $40.5 |  |  |  | $3,320.0 |
Depreciation and amortization | 367.0 |  |  | 34.2 |  |  | 2.1 |  |  | 403.3 |  |  | 8.3 |  |  | 411.6 |
Operating income (loss) | 571.9 |  |  | 30.7 |  |  | (4.8 | ) |  | 597.8 |  |  | (60.8 | ) |  | 537.0 |
Interest expense |  |  |  |  |  |  | 194.6 |  |  | 1.6 |  |  | 196.2 |
Equity (income) loss from unconsolidated investments, net | (39.8 | ) |  | — |  |  | — |  |  | (39.8 | ) |  | 0.2 |  |  | (39.6 | )
Income tax expense (benefit) |  |  |  |  |  |  | 87.4 |  |  | (28.0 | ) |  | 59.4 |
Net income (loss) attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 406.0 |  |  | (34.5 | ) |  | 371.5 |
Total assets | 11,040.5 |  |  | 1,091.1 |  |  | 781.0 |  |  | 12,912.6 |  |  | 461.2 |  |  | 13,373.8 |
Investments in equity method subsidiaries | 325.3 |  |  | — |  |  | — |  |  | 325.3 |  |  | 0.7 |  |  | 326.0 |
Construction and acquisition expenditures | 1,005.5 |  |  | 137.1 |  |  | 0.1 |  |  | 1,142.7 |  |  | 54.1 |  |  | 1,196.8 |
| Utility |  | Non-Regulated, |  | Alliant Energy
2015 | Electric |  | Gas |  | Other |  | Total |  | Parent and Other |  | Consolidated
Operating revenues |  | $2,770.5 |  |  |  | $381.2 |  |  |  | $57.9 |  |  |  | $3,209.6 |  |  |  | $44.0 |  |  |  | $3,253.6 |
Depreciation and amortization | 358.6 |  |  | 31.1 |  |  | 1.8 |  |  | 391.5 |  |  | 9.8 |  |  | 401.3 |
Operating income | 514.1 |  |  | 34.6 |  |  | 1.9 |  |  | 550.6 |  |  | 26.4 |  |  | 577.0 |
Interest expense |  |  |  |  |  |  | 189.2 |  |  | (2.1 | ) |  | 187.1 |
Equity (income) loss from unconsolidated investments, net | (35.1 | ) |  | — |  |  | — |  |  | (35.1 | ) |  | 1.3 |  |  | (33.8 | )
Income taxes |  |  |  |  |  |  | 60.2 |  |  | 10.2 |  |  | 70.4 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 362.3 |  |  | 15.9 |  |  | 378.2 |
Total assets | 10,211.3 |  |  | 939.3 |  |  | 828.9 |  |  | 11,979.5 |  |  | 515.7 |  |  | 12,495.2 |
Investments in equity method subsidiaries | 302.0 |  |  | — |  |  | — |  |  | 302.0 |  |  | 0.9 |  |  | 302.9 |
Construction and acquisition expenditures | 855.8 |  |  | 106.4 |  |  | 1.4 |  |  | 963.6 |  |  | 70.7 |  |  | 1,034.3 |
| Utility |  | Non-Regulated, |  | Alliant Energy
2014 | Electric |  | Gas |  | Other |  | Total |  | Parent and Other |  | Consolidated
Operating revenues |  | $2,713.6 |  |  |  | $517.5 |  |  |  | $66.1 |  |  |  | $3,297.2 |  |  |  | $53.1 |  |  |  | $3,350.3 |
Depreciation and amortization | 347.0 |  |  | 29.9 |  |  | 1.8 |  |  | 378.7 |  |  | 9.4 |  |  | 388.1 |
Operating income | 442.4 |  |  | 53.8 |  |  | 14.0 |  |  | 510.2 |  |  | 33.4 |  |  | 543.6 |
Interest expense |  |  |  |  |  |  | 176.3 |  |  | 4.3 |  |  | 180.6 |
Equity income (loss) from unconsolidated investments, net | (42.8 | ) |  | — |  |  | — |  |  | (42.8 | ) |  | 2.4 |  |  | (40.4 | )
Income taxes |  |  |  |  |  |  | 36.4 |  |  | 7.9 |  |  | 44.3 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 362.0 |  |  | 21.1 |  |  | 383.1 |
Total assets | 9,660.4 |  |  | 913.5 |  |  | 993.9 |  |  | 11,567.8 |  |  | 495.7 |  |  | 12,063.5 |
Investments in equity method subsidiaries | 294.3 |  |  | — |  |  | — |  |  | 294.3 |  |  | 2.3 |  |  | 296.6 |
Construction and acquisition expenditures | 774.8 |  |  | 63.2 |  |  | 0.9 |  |  | 838.9 |  |  | 63.9 |  |  | 902.8 |
IPL - IPL is a utility primarily serving retail customers in Iowa and includes three reportable segments: a) electric operations; b) gas operations; and c) other, which includes steam operations and the unallocated portions of the utility business. Various line items in the following tables are not allocated to the electric and gas segments for management reporting purposes, and therefore, are included only in “Total.” Intersegment revenues were not material to IPL’s operations and there was no single customer whose revenues were 10% or more of IPL’s consolidated revenues. All of IPL’s operations and assets are located in the U.S. Certain financial information relating to IPL’s business segments, which represent the services provided to its customers, was as follows (in millions):
2016 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,569.7 |  |  |  | $204.0 |  |  |  | $46.7 |  |  |  | $1,820.4 |
Depreciation and amortization | 189.4 |  |  | 19.3 |  |  | 2.1 |  |  | 210.8 |
Operating income | 252.0 |  |  | 15.5 |  |  | 3.3 |  |  | 270.8 |
Interest expense |  |  |  |  |  |  | 103.2 |
Income tax benefit |  |  |  |  |  |  | (5.9 | )
Earnings available for common stock |  |  |  |  |  |  | 215.6 |
Total assets | 6,278.2 |  |  | 653.3 |  |  | 373.2 |  |  | 7,304.7 |
Construction and acquisition expenditures | 598.1 |  |  | 91.5 |  |  | 0.1 |  |  | 689.7 |
2015 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,503.8 |  |  |  | $217.3 |  |  |  | $53.4 |  |  |  | $1,774.5 |
Depreciation and amortization | 187.9 |  |  | 17.5 |  |  | 1.8 |  |  | 207.2 |
Operating income | 218.8 |  |  | 17.7 |  |  | 5.4 |  |  | 241.9 |
Interest expense |  |  |  |  |  |  | 96.8 |
Income tax benefit |  |  |  |  |  |  | (22.7 | )
Earnings available for common stock |  |  |  |  |  |  | 186.0 |
Total assets | 5,754.1 |  |  | 548.2 |  |  | 406.8 |  |  | 6,709.1 |
Construction and acquisition expenditures | 561.2 |  |  | 56.7 |  |  | 1.4 |  |  | 619.3 |
2014 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,493.3 |  |  |  | $296.5 |  |  |  | $58.3 |  |  |  | $1,848.1 |
Depreciation and amortization | 178.7 |  |  | 17.0 |  |  | 1.8 |  |  | 197.5 |
Operating income | 166.8 |  |  | 25.7 |  |  | 16.7 |  |  | 209.2 |
Interest expense |  |  |  |  |  |  | 89.9 |
Income tax benefit |  |  |  |  |  |  | (48.9 | )
Earnings available for common stock |  |  |  |  |  |  | 181.6 |
Total assets | 5,398.3 |  |  | 544.1 |  |  | 507.8 |  |  | 6,450.2 |
Construction and acquisition expenditures | 490.0 |  |  | 35.1 |  |  | 0.9 |  |  | 526.0 |
WPL - WPL is a utility serving customers in Wisconsin and includes three reportable segments: a) electric operations; b) gas operations; and c) other, which includes the unallocated portions of the utility business. Various line items in the following tables are not allocated to the electric and gas segments for management reporting purposes, and therefore, are included only in “Total.” Intersegment revenues were not material to WPL’s operations and there was no single customer whose revenues were 10% or more of WPL’s consolidated revenues. All of WPL’s operations and assets are located in the U.S. Certain financial information relating to WPL’s business segments, which represent the services provided to its customers, was as follows (in millions):
2016 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,305.8 |  |  |  | $151.4 |  |  |  | $1.9 |  |  |  | $1,459.1 |
Depreciation and amortization | 177.6 |  |  | 14.9 |  |  | — |  |  | 192.5 |
Operating income (loss) | 319.9 |  |  | 15.2 |  |  | (8.1 | ) |  | 327.0 |
Interest expense |  |  |  |  |  |  | 91.4 |
Equity income from unconsolidated investments | (39.8 | ) |  | — |  |  | — |  |  | (39.8 | )
Income taxes |  |  |  |  |  |  | 93.3 |
Earnings available for common stock |  |  |  |  |  |  | 190.4 |
Total assets | 4,444.7 |  |  | 437.8 |  |  | 407.8 |  |  | 5,290.3 |
Investments in equity method subsidiaries | 7.7 |  |  | — |  |  | — |  |  | 7.7 |
Construction and acquisition expenditures | 407.4 |  |  | 45.6 |  |  | — |  |  | 453.0 |
2015 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,266.7 |  |  |  | $163.9 |  |  |  | $4.5 |  |  |  | $1,435.1 |
Depreciation and amortization | 170.7 |  |  | 13.6 |  |  | — |  |  | 184.3 |
Operating income (loss) | 295.3 |  |  | 16.9 |  |  | (3.5 | ) |  | 308.7 |
Interest expense |  |  |  |  |  |  | 92.4 |
Equity income from unconsolidated investments | (35.1 | ) |  | — |  |  | — |  |  | (35.1 | )
Income taxes |  |  |  |  |  |  | 82.9 |
Earnings available for common stock |  |  |  |  |  |  | 176.3 |
Total assets | 4,457.2 |  |  | 391.1 |  |  | 422.1 |  |  | 5,270.4 |
Investments in equity method subsidiaries | 302.0 |  |  | — |  |  | — |  |  | 302.0 |
Construction and acquisition expenditures | 294.6 |  |  | 49.7 |  |  | — |  |  | 344.3 |
2014 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,220.3 |  |  |  | $221.0 |  |  |  | $7.8 |  |  |  | $1,449.1 |
Depreciation and amortization | 168.3 |  |  | 12.9 |  |  | — |  |  | 181.2 |
Operating income (loss) | 275.6 |  |  | 28.1 |  |  | (2.7 | ) |  | 301.0 |
Interest expense |  |  |  |  |  |  | 86.4 |
Equity income from unconsolidated investments | (42.8 | ) |  | — |  |  | — |  |  | (42.8 | )
Income taxes |  |  |  |  |  |  | 85.3 |
Earnings available for common stock |  |  |  |  |  |  | 180.4 |
Total assets | 4,262.1 |  |  | 369.4 |  |  | 486.1 |  |  | 5,117.6 |
Investments in equity method subsidiaries | 294.3 |  |  | — |  |  | — |  |  | 294.3 |
Construction and acquisition expenditures | 284.8 |  |  | 28.1 |  |  | — |  |  | 312.9 |
IPL [Member] |
Segment Reporting Information [Line Items] |
Segments Of Business | SEGMENTS OF BUSINESS Alliant Energy - Alliant Energy’s principal businesses as of December 31, 2016 are:
• | Utility - includes the operations of IPL and WPL, which primarily serve retail customers in Iowa and Wisconsin. The utility business has three reportable segments: a) utility electric operations, which include Alliant Energy’s investment in ATC; b) utility gas operations; and c) utility other, which includes steam operations and the unallocated portions of the utility business. Various line items in the following tables are not allocated to the electric and gas segments for management reporting purposes, and therefore, are included only in “Total Utility.”
• | Non-regulated, Parent and Other - includes the operations of AEF and its subsidiaries, Corporate Services, the Alliant Energy parent company, and any Alliant Energy parent company consolidating adjustments. AEF’s businesses include Transportation, Non-regulated Generation and other non-regulated investments described in Note 1(a).
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. Intersegment revenues were not material to Alliant Energy’s operations and there was no single customer whose revenues were 10% or more of Alliant Energy’s consolidated revenues. All of Alliant Energy’s operations and assets are located in the U.S. Certain financial information relating to Alliant Energy’s business segments, which represent the services provided to its customers, was as follows (in millions):
| Utility |  | Non-Regulated, |  | Alliant Energy
2016 | Electric |  | Gas |  | Other |  | Total |  | Parent and Other |  | Consolidated
Operating revenues |  | $2,875.5 |  |  |  | $355.4 |  |  |  | $48.6 |  |  |  | $3,279.5 |  |  |  | $40.5 |  |  |  | $3,320.0 |
Depreciation and amortization | 367.0 |  |  | 34.2 |  |  | 2.1 |  |  | 403.3 |  |  | 8.3 |  |  | 411.6 |
Operating income (loss) | 571.9 |  |  | 30.7 |  |  | (4.8 | ) |  | 597.8 |  |  | (60.8 | ) |  | 537.0 |
Interest expense |  |  |  |  |  |  | 194.6 |  |  | 1.6 |  |  | 196.2 |
Equity (income) loss from unconsolidated investments, net | (39.8 | ) |  | — |  |  | — |  |  | (39.8 | ) |  | 0.2 |  |  | (39.6 | )
Income tax expense (benefit) |  |  |  |  |  |  | 87.4 |  |  | (28.0 | ) |  | 59.4 |
Net income (loss) attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 406.0 |  |  | (34.5 | ) |  | 371.5 |
Total assets | 11,040.5 |  |  | 1,091.1 |  |  | 781.0 |  |  | 12,912.6 |  |  | 461.2 |  |  | 13,373.8 |
Investments in equity method subsidiaries | 325.3 |  |  | — |  |  | — |  |  | 325.3 |  |  | 0.7 |  |  | 326.0 |
Construction and acquisition expenditures | 1,005.5 |  |  | 137.1 |  |  | 0.1 |  |  | 1,142.7 |  |  | 54.1 |  |  | 1,196.8 |
| Utility |  | Non-Regulated, |  | Alliant Energy
2015 | Electric |  | Gas |  | Other |  | Total |  | Parent and Other |  | Consolidated
Operating revenues |  | $2,770.5 |  |  |  | $381.2 |  |  |  | $57.9 |  |  |  | $3,209.6 |  |  |  | $44.0 |  |  |  | $3,253.6 |
Depreciation and amortization | 358.6 |  |  | 31.1 |  |  | 1.8 |  |  | 391.5 |  |  | 9.8 |  |  | 401.3 |
Operating income | 514.1 |  |  | 34.6 |  |  | 1.9 |  |  | 550.6 |  |  | 26.4 |  |  | 577.0 |
Interest expense |  |  |  |  |  |  | 189.2 |  |  | (2.1 | ) |  | 187.1 |
Equity (income) loss from unconsolidated investments, net | (35.1 | ) |  | — |  |  | — |  |  | (35.1 | ) |  | 1.3 |  |  | (33.8 | )
Income taxes |  |  |  |  |  |  | 60.2 |  |  | 10.2 |  |  | 70.4 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 362.3 |  |  | 15.9 |  |  | 378.2 |
Total assets | 10,211.3 |  |  | 939.3 |  |  | 828.9 |  |  | 11,979.5 |  |  | 515.7 |  |  | 12,495.2 |
Investments in equity method subsidiaries | 302.0 |  |  | — |  |  | — |  |  | 302.0 |  |  | 0.9 |  |  | 302.9 |
Construction and acquisition expenditures | 855.8 |  |  | 106.4 |  |  | 1.4 |  |  | 963.6 |  |  | 70.7 |  |  | 1,034.3 |
| Utility |  | Non-Regulated, |  | Alliant Energy
2014 | Electric |  | Gas |  | Other |  | Total |  | Parent and Other |  | Consolidated
Operating revenues |  | $2,713.6 |  |  |  | $517.5 |  |  |  | $66.1 |  |  |  | $3,297.2 |  |  |  | $53.1 |  |  |  | $3,350.3 |
Depreciation and amortization | 347.0 |  |  | 29.9 |  |  | 1.8 |  |  | 378.7 |  |  | 9.4 |  |  | 388.1 |
Operating income | 442.4 |  |  | 53.8 |  |  | 14.0 |  |  | 510.2 |  |  | 33.4 |  |  | 543.6 |
Interest expense |  |  |  |  |  |  | 176.3 |  |  | 4.3 |  |  | 180.6 |
Equity income (loss) from unconsolidated investments, net | (42.8 | ) |  | — |  |  | — |  |  | (42.8 | ) |  | 2.4 |  |  | (40.4 | )
Income taxes |  |  |  |  |  |  | 36.4 |  |  | 7.9 |  |  | 44.3 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 362.0 |  |  | 21.1 |  |  | 383.1 |
Total assets | 9,660.4 |  |  | 913.5 |  |  | 993.9 |  |  | 11,567.8 |  |  | 495.7 |  |  | 12,063.5 |
Investments in equity method subsidiaries | 294.3 |  |  | — |  |  | — |  |  | 294.3 |  |  | 2.3 |  |  | 296.6 |
Construction and acquisition expenditures | 774.8 |  |  | 63.2 |  |  | 0.9 |  |  | 838.9 |  |  | 63.9 |  |  | 902.8 |
IPL - IPL is a utility primarily serving retail customers in Iowa and includes three reportable segments: a) electric operations; b) gas operations; and c) other, which includes steam operations and the unallocated portions of the utility business. Various line items in the following tables are not allocated to the electric and gas segments for management reporting purposes, and therefore, are included only in “Total.” Intersegment revenues were not material to IPL’s operations and there was no single customer whose revenues were 10% or more of IPL’s consolidated revenues. All of IPL’s operations and assets are located in the U.S. Certain financial information relating to IPL’s business segments, which represent the services provided to its customers, was as follows (in millions):
2016 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,569.7 |  |  |  | $204.0 |  |  |  | $46.7 |  |  |  | $1,820.4 |
Depreciation and amortization | 189.4 |  |  | 19.3 |  |  | 2.1 |  |  | 210.8 |
Operating income | 252.0 |  |  | 15.5 |  |  | 3.3 |  |  | 270.8 |
Interest expense |  |  |  |  |  |  | 103.2 |
Income tax benefit |  |  |  |  |  |  | (5.9 | )
Earnings available for common stock |  |  |  |  |  |  | 215.6 |
Total assets | 6,278.2 |  |  | 653.3 |  |  | 373.2 |  |  | 7,304.7 |
Construction and acquisition expenditures | 598.1 |  |  | 91.5 |  |  | 0.1 |  |  | 689.7 |
2015 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,503.8 |  |  |  | $217.3 |  |  |  | $53.4 |  |  |  | $1,774.5 |
Depreciation and amortization | 187.9 |  |  | 17.5 |  |  | 1.8 |  |  | 207.2 |
Operating income | 218.8 |  |  | 17.7 |  |  | 5.4 |  |  | 241.9 |
Interest expense |  |  |  |  |  |  | 96.8 |
Income tax benefit |  |  |  |  |  |  | (22.7 | )
Earnings available for common stock |  |  |  |  |  |  | 186.0 |
Total assets | 5,754.1 |  |  | 548.2 |  |  | 406.8 |  |  | 6,709.1 |
Construction and acquisition expenditures | 561.2 |  |  | 56.7 |  |  | 1.4 |  |  | 619.3 |
2014 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,493.3 |  |  |  | $296.5 |  |  |  | $58.3 |  |  |  | $1,848.1 |
Depreciation and amortization | 178.7 |  |  | 17.0 |  |  | 1.8 |  |  | 197.5 |
Operating income | 166.8 |  |  | 25.7 |  |  | 16.7 |  |  | 209.2 |
Interest expense |  |  |  |  |  |  | 89.9 |
Income tax benefit |  |  |  |  |  |  | (48.9 | )
Earnings available for common stock |  |  |  |  |  |  | 181.6 |
Total assets | 5,398.3 |  |  | 544.1 |  |  | 507.8 |  |  | 6,450.2 |
Construction and acquisition expenditures | 490.0 |  |  | 35.1 |  |  | 0.9 |  |  | 526.0 |
WPL - WPL is a utility serving customers in Wisconsin and includes three reportable segments: a) electric operations; b) gas operations; and c) other, which includes the unallocated portions of the utility business. Various line items in the following tables are not allocated to the electric and gas segments for management reporting purposes, and therefore, are included only in “Total.” Intersegment revenues were not material to WPL’s operations and there was no single customer whose revenues were 10% or more of WPL’s consolidated revenues. All of WPL’s operations and assets are located in the U.S. Certain financial information relating to WPL’s business segments, which represent the services provided to its customers, was as follows (in millions):
2016 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,305.8 |  |  |  | $151.4 |  |  |  | $1.9 |  |  |  | $1,459.1 |
Depreciation and amortization | 177.6 |  |  | 14.9 |  |  | — |  |  | 192.5 |
Operating income (loss) | 319.9 |  |  | 15.2 |  |  | (8.1 | ) |  | 327.0 |
Interest expense |  |  |  |  |  |  | 91.4 |
Equity income from unconsolidated investments | (39.8 | ) |  | — |  |  | — |  |  | (39.8 | )
Income taxes |  |  |  |  |  |  | 93.3 |
Earnings available for common stock |  |  |  |  |  |  | 190.4 |
Total assets | 4,444.7 |  |  | 437.8 |  |  | 407.8 |  |  | 5,290.3 |
Investments in equity method subsidiaries | 7.7 |  |  | — |  |  | — |  |  | 7.7 |
Construction and acquisition expenditures | 407.4 |  |  | 45.6 |  |  | — |  |  | 453.0 |
2015 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,266.7 |  |  |  | $163.9 |  |  |  | $4.5 |  |  |  | $1,435.1 |
Depreciation and amortization | 170.7 |  |  | 13.6 |  |  | — |  |  | 184.3 |
Operating income (loss) | 295.3 |  |  | 16.9 |  |  | (3.5 | ) |  | 308.7 |
Interest expense |  |  |  |  |  |  | 92.4 |
Equity income from unconsolidated investments | (35.1 | ) |  | — |  |  | — |  |  | (35.1 | )
Income taxes |  |  |  |  |  |  | 82.9 |
Earnings available for common stock |  |  |  |  |  |  | 176.3 |
Total assets | 4,457.2 |  |  | 391.1 |  |  | 422.1 |  |  | 5,270.4 |
Investments in equity method subsidiaries | 302.0 |  |  | — |  |  | — |  |  | 302.0 |
Construction and acquisition expenditures | 294.6 |  |  | 49.7 |  |  | — |  |  | 344.3 |
2014 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,220.3 |  |  |  | $221.0 |  |  |  | $7.8 |  |  |  | $1,449.1 |
Depreciation and amortization | 168.3 |  |  | 12.9 |  |  | — |  |  | 181.2 |
Operating income (loss) | 275.6 |  |  | 28.1 |  |  | (2.7 | ) |  | 301.0 |
Interest expense |  |  |  |  |  |  | 86.4 |
Equity income from unconsolidated investments | (42.8 | ) |  | — |  |  | — |  |  | (42.8 | )
Income taxes |  |  |  |  |  |  | 85.3 |
Earnings available for common stock |  |  |  |  |  |  | 180.4 |
Total assets | 4,262.1 |  |  | 369.4 |  |  | 486.1 |  |  | 5,117.6 |
Investments in equity method subsidiaries | 294.3 |  |  | — |  |  | — |  |  | 294.3 |
Construction and acquisition expenditures | 284.8 |  |  | 28.1 |  |  | — |  |  | 312.9 |
WPL [Member] |
Segment Reporting Information [Line Items] |
Segments Of Business | SEGMENTS OF BUSINESS Alliant Energy - Alliant Energy’s principal businesses as of December 31, 2016 are:
• | Utility - includes the operations of IPL and WPL, which primarily serve retail customers in Iowa and Wisconsin. The utility business has three reportable segments: a) utility electric operations, which include Alliant Energy’s investment in ATC; b) utility gas operations; and c) utility other, which includes steam operations and the unallocated portions of the utility business. Various line items in the following tables are not allocated to the electric and gas segments for management reporting purposes, and therefore, are included only in “Total Utility.”
• | Non-regulated, Parent and Other - includes the operations of AEF and its subsidiaries, Corporate Services, the Alliant Energy parent company, and any Alliant Energy parent company consolidating adjustments. AEF’s businesses include Transportation, Non-regulated Generation and other non-regulated investments described in Note 1(a).
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. Intersegment revenues were not material to Alliant Energy’s operations and there was no single customer whose revenues were 10% or more of Alliant Energy’s consolidated revenues. All of Alliant Energy’s operations and assets are located in the U.S. Certain financial information relating to Alliant Energy’s business segments, which represent the services provided to its customers, was as follows (in millions):
| Utility |  | Non-Regulated, |  | Alliant Energy
2016 | Electric |  | Gas |  | Other |  | Total |  | Parent and Other |  | Consolidated
Operating revenues |  | $2,875.5 |  |  |  | $355.4 |  |  |  | $48.6 |  |  |  | $3,279.5 |  |  |  | $40.5 |  |  |  | $3,320.0 |
Depreciation and amortization | 367.0 |  |  | 34.2 |  |  | 2.1 |  |  | 403.3 |  |  | 8.3 |  |  | 411.6 |
Operating income (loss) | 571.9 |  |  | 30.7 |  |  | (4.8 | ) |  | 597.8 |  |  | (60.8 | ) |  | 537.0 |
Interest expense |  |  |  |  |  |  | 194.6 |  |  | 1.6 |  |  | 196.2 |
Equity (income) loss from unconsolidated investments, net | (39.8 | ) |  | — |  |  | — |  |  | (39.8 | ) |  | 0.2 |  |  | (39.6 | )
Income tax expense (benefit) |  |  |  |  |  |  | 87.4 |  |  | (28.0 | ) |  | 59.4 |
Net income (loss) attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 406.0 |  |  | (34.5 | ) |  | 371.5 |
Total assets | 11,040.5 |  |  | 1,091.1 |  |  | 781.0 |  |  | 12,912.6 |  |  | 461.2 |  |  | 13,373.8 |
Investments in equity method subsidiaries | 325.3 |  |  | — |  |  | — |  |  | 325.3 |  |  | 0.7 |  |  | 326.0 |
Construction and acquisition expenditures | 1,005.5 |  |  | 137.1 |  |  | 0.1 |  |  | 1,142.7 |  |  | 54.1 |  |  | 1,196.8 |
| Utility |  | Non-Regulated, |  | Alliant Energy
2015 | Electric |  | Gas |  | Other |  | Total |  | Parent and Other |  | Consolidated
Operating revenues |  | $2,770.5 |  |  |  | $381.2 |  |  |  | $57.9 |  |  |  | $3,209.6 |  |  |  | $44.0 |  |  |  | $3,253.6 |
Depreciation and amortization | 358.6 |  |  | 31.1 |  |  | 1.8 |  |  | 391.5 |  |  | 9.8 |  |  | 401.3 |
Operating income | 514.1 |  |  | 34.6 |  |  | 1.9 |  |  | 550.6 |  |  | 26.4 |  |  | 577.0 |
Interest expense |  |  |  |  |  |  | 189.2 |  |  | (2.1 | ) |  | 187.1 |
Equity (income) loss from unconsolidated investments, net | (35.1 | ) |  | — |  |  | — |  |  | (35.1 | ) |  | 1.3 |  |  | (33.8 | )
Income taxes |  |  |  |  |  |  | 60.2 |  |  | 10.2 |  |  | 70.4 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 362.3 |  |  | 15.9 |  |  | 378.2 |
Total assets | 10,211.3 |  |  | 939.3 |  |  | 828.9 |  |  | 11,979.5 |  |  | 515.7 |  |  | 12,495.2 |
Investments in equity method subsidiaries | 302.0 |  |  | — |  |  | — |  |  | 302.0 |  |  | 0.9 |  |  | 302.9 |
Construction and acquisition expenditures | 855.8 |  |  | 106.4 |  |  | 1.4 |  |  | 963.6 |  |  | 70.7 |  |  | 1,034.3 |
| Utility |  | Non-Regulated, |  | Alliant Energy
2014 | Electric |  | Gas |  | Other |  | Total |  | Parent and Other |  | Consolidated
Operating revenues |  | $2,713.6 |  |  |  | $517.5 |  |  |  | $66.1 |  |  |  | $3,297.2 |  |  |  | $53.1 |  |  |  | $3,350.3 |
Depreciation and amortization | 347.0 |  |  | 29.9 |  |  | 1.8 |  |  | 378.7 |  |  | 9.4 |  |  | 388.1 |
Operating income | 442.4 |  |  | 53.8 |  |  | 14.0 |  |  | 510.2 |  |  | 33.4 |  |  | 543.6 |
Interest expense |  |  |  |  |  |  | 176.3 |  |  | 4.3 |  |  | 180.6 |
Equity income (loss) from unconsolidated investments, net | (42.8 | ) |  | — |  |  | — |  |  | (42.8 | ) |  | 2.4 |  |  | (40.4 | )
Income taxes |  |  |  |  |  |  | 36.4 |  |  | 7.9 |  |  | 44.3 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 362.0 |  |  | 21.1 |  |  | 383.1 |
Total assets | 9,660.4 |  |  | 913.5 |  |  | 993.9 |  |  | 11,567.8 |  |  | 495.7 |  |  | 12,063.5 |
Investments in equity method subsidiaries | 294.3 |  |  | — |  |  | — |  |  | 294.3 |  |  | 2.3 |  |  | 296.6 |
Construction and acquisition expenditures | 774.8 |  |  | 63.2 |  |  | 0.9 |  |  | 838.9 |  |  | 63.9 |  |  | 902.8 |
IPL - IPL is a utility primarily serving retail customers in Iowa and includes three reportable segments: a) electric operations; b) gas operations; and c) other, which includes steam operations and the unallocated portions of the utility business. Various line items in the following tables are not allocated to the electric and gas segments for management reporting purposes, and therefore, are included only in “Total.” Intersegment revenues were not material to IPL’s operations and there was no single customer whose revenues were 10% or more of IPL’s consolidated revenues. All of IPL’s operations and assets are located in the U.S. Certain financial information relating to IPL’s business segments, which represent the services provided to its customers, was as follows (in millions):
2016 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,569.7 |  |  |  | $204.0 |  |  |  | $46.7 |  |  |  | $1,820.4 |
Depreciation and amortization | 189.4 |  |  | 19.3 |  |  | 2.1 |  |  | 210.8 |
Operating income | 252.0 |  |  | 15.5 |  |  | 3.3 |  |  | 270.8 |
Interest expense |  |  |  |  |  |  | 103.2 |
Income tax benefit |  |  |  |  |  |  | (5.9 | )
Earnings available for common stock |  |  |  |  |  |  | 215.6 |
Total assets | 6,278.2 |  |  | 653.3 |  |  | 373.2 |  |  | 7,304.7 |
Construction and acquisition expenditures | 598.1 |  |  | 91.5 |  |  | 0.1 |  |  | 689.7 |
2015 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,503.8 |  |  |  | $217.3 |  |  |  | $53.4 |  |  |  | $1,774.5 |
Depreciation and amortization | 187.9 |  |  | 17.5 |  |  | 1.8 |  |  | 207.2 |
Operating income | 218.8 |  |  | 17.7 |  |  | 5.4 |  |  | 241.9 |
Interest expense |  |  |  |  |  |  | 96.8 |
Income tax benefit |  |  |  |  |  |  | (22.7 | )
Earnings available for common stock |  |  |  |  |  |  | 186.0 |
Total assets | 5,754.1 |  |  | 548.2 |  |  | 406.8 |  |  | 6,709.1 |
Construction and acquisition expenditures | 561.2 |  |  | 56.7 |  |  | 1.4 |  |  | 619.3 |
2014 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,493.3 |  |  |  | $296.5 |  |  |  | $58.3 |  |  |  | $1,848.1 |
Depreciation and amortization | 178.7 |  |  | 17.0 |  |  | 1.8 |  |  | 197.5 |
Operating income | 166.8 |  |  | 25.7 |  |  | 16.7 |  |  | 209.2 |
Interest expense |  |  |  |  |  |  | 89.9 |
Income tax benefit |  |  |  |  |  |  | (48.9 | )
Earnings available for common stock |  |  |  |  |  |  | 181.6 |
Total assets | 5,398.3 |  |  | 544.1 |  |  | 507.8 |  |  | 6,450.2 |
Construction and acquisition expenditures | 490.0 |  |  | 35.1 |  |  | 0.9 |  |  | 526.0 |
WPL - WPL is a utility serving customers in Wisconsin and includes three reportable segments: a) electric operations; b) gas operations; and c) other, which includes the unallocated portions of the utility business. Various line items in the following tables are not allocated to the electric and gas segments for management reporting purposes, and therefore, are included only in “Total.” Intersegment revenues were not material to WPL’s operations and there was no single customer whose revenues were 10% or more of WPL’s consolidated revenues. All of WPL’s operations and assets are located in the U.S. Certain financial information relating to WPL’s business segments, which represent the services provided to its customers, was as follows (in millions):
2016 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,305.8 |  |  |  | $151.4 |  |  |  | $1.9 |  |  |  | $1,459.1 |
Depreciation and amortization | 177.6 |  |  | 14.9 |  |  | — |  |  | 192.5 |
Operating income (loss) | 319.9 |  |  | 15.2 |  |  | (8.1 | ) |  | 327.0 |
Interest expense |  |  |  |  |  |  | 91.4 |
Equity income from unconsolidated investments | (39.8 | ) |  | — |  |  | — |  |  | (39.8 | )
Income taxes |  |  |  |  |  |  | 93.3 |
Earnings available for common stock |  |  |  |  |  |  | 190.4 |
Total assets | 4,444.7 |  |  | 437.8 |  |  | 407.8 |  |  | 5,290.3 |
Investments in equity method subsidiaries | 7.7 |  |  | — |  |  | — |  |  | 7.7 |
Construction and acquisition expenditures | 407.4 |  |  | 45.6 |  |  | — |  |  | 453.0 |
2015 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,266.7 |  |  |  | $163.9 |  |  |  | $4.5 |  |  |  | $1,435.1 |
Depreciation and amortization | 170.7 |  |  | 13.6 |  |  | — |  |  | 184.3 |
Operating income (loss) | 295.3 |  |  | 16.9 |  |  | (3.5 | ) |  | 308.7 |
Interest expense |  |  |  |  |  |  | 92.4 |
Equity income from unconsolidated investments | (35.1 | ) |  | — |  |  | — |  |  | (35.1 | )
Income taxes |  |  |  |  |  |  | 82.9 |
Earnings available for common stock |  |  |  |  |  |  | 176.3 |
Total assets | 4,457.2 |  |  | 391.1 |  |  | 422.1 |  |  | 5,270.4 |
Investments in equity method subsidiaries | 302.0 |  |  | — |  |  | — |  |  | 302.0 |
Construction and acquisition expenditures | 294.6 |  |  | 49.7 |  |  | — |  |  | 344.3 |
2014 | Electric |  | Gas |  | Other |  | Total
Operating revenues |  | $1,220.3 |  |  |  | $221.0 |  |  |  | $7.8 |  |  |  | $1,449.1 |
Depreciation and amortization | 168.3 |  |  | 12.9 |  |  | — |  |  | 181.2 |
Operating income (loss) | 275.6 |  |  | 28.1 |  |  | (2.7 | ) |  | 301.0 |
Interest expense |  |  |  |  |  |  | 86.4 |
Equity income from unconsolidated investments | (42.8 | ) |  | — |  |  | — |  |  | (42.8 | )
Income taxes |  |  |  |  |  |  | 85.3 |
Earnings available for common stock |  |  |  |  |  |  | 180.4 |
Total assets | 4,262.1 |  |  | 369.4 |  |  | 486.1 |  |  | 5,117.6 |
Investments in equity method subsidiaries | 294.3 |  |  | — |  |  | — |  |  | 294.3 |
Construction and acquisition expenditures | 284.8 |  |  | 28.1 |  |  | — |  |  | 312.9 |

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