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Segments Of Business

12 Months Ended

Dec. 31, 2021

Segment Reporting Information [Line Items]

Segments Of Business

SEGMENTS OF BUSINESS

Alliant Energy - Alliant Energy’s principal businesses as of December 31, 2021 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; 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.”

•ATC Holdings, Non-utility, 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 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.

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):

																											ATC Holdings,
			Utility																								Non-utility,						Alliant Energy
2021			Electric						Gas						Other						Total						Parent and Other						Consolidated
Revenues			$3,081						$456						$49						$3,586						$83						$3,669
Depreciation and amortization			591						54						6						651						6						657
Operating income (loss)			716						63						(11)						768						27						795
Interest expense																					244						33						277
Equity income from unconsolidated investments, net			(2)						—						—						(2)						(60)						(62)
Income tax expense (benefit)																					(87)						13						(74)
Net income attributable to Alliant Energy common shareowners																					618						41						659
Total assets			14,924						1,487						1,103						17,514						1,039						18,553
Investments in equity method subsidiaries			17						—						—						17						491						508
Construction and acquisition expenditures			980						90						—						1,070						99						1,169

																											ATC Holdings,
			Utility																								Non-utility,						Alliant Energy
2020			Electric						Gas						Other						Total						Parent and Other						Consolidated
Revenues			$2,920						$373						$49						$3,342						$74						$3,416
Depreciation and amortization			556						49						5						610						5						615
Operating income (loss)			643						74						(1)						716						24						740
Interest expense																					243						32						275
Equity income from unconsolidated investments, net			(2)						—						—						(2)						(59)						(61)
Income tax expense (benefit)																					(66)						9						(57)
Net income attributable to Alliant Energy common shareowners																					573						41						614
Total assets			14,358						1,413						990						16,761						949						17,710
Investments in equity method subsidiaries			11						—						—						11						465						476
Construction and acquisition expenditures			1,109						182						2						1,293						73						1,366

																											ATC Holdings,
			Utility																								Non-utility,						Alliant Energy
2019			Electric						Gas						Other						Total						Parent and Other						Consolidated
Revenues			$3,064						$455						$46						$3,565						$83						$3,648
Depreciation and amortization			513						47						3						563						4						567
Operating income			679						70						1						750						28						778
Interest expense																					229						44						273
Equity income from unconsolidated investments, net			(1)						—						—						(1)						(52)						(53)
Income tax expense (benefit)																					73						(4)						69
Net income attributable to Alliant Energy common shareowners																					517						40						557
Total assets			13,659						1,269						856						15,784						917						16,701
Investments in equity method subsidiaries			9						—						—						9						449						458
Construction and acquisition expenditures			1,439						100						—						1,539						101						1,640

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):

2021			Electric						Gas						Other						Total
Revenues			$1,752						$265						$46						$2,063
Depreciation and amortization			338						31						6						375
Operating income (loss)			420						43						(3)						460
Interest expense																					139
Income tax benefit																					(36)
Net income available for common stock																					350
Total assets			8,602						819						575						9,996
Construction and acquisition expenditures			342						42						—						384

2020			Electric						Gas						Other						Total
Revenues			$1,695						$208						$44						$1,947
Depreciation and amortization			321						30						5						356
Operating income			358						50						2						410
Interest expense																					139
Income tax benefit																					(47)
Net income available for common stock																					324
Total assets			8,518						766						565						9,849
Construction and acquisition expenditures			626						59						2						687

2019			Electric						Gas						Other						Total
Revenues			$1,781						$264						$44						$2,089
Depreciation and amortization			295						29						3						327
Operating income			360						39						4						403
Interest expense																					127
Income taxes																					24
Net income available for common stock																					284
Total assets			8,075						734						468						9,277
Construction and acquisition expenditures			964						56						—						1,020

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):

2021			Electric						Gas						Other						Total
Revenues			$1,329						$191						$3						$1,523
Depreciation and amortization			253						23						—						276
Operating income (loss)			296						20						(8)						308
Interest expense																					105
Income tax benefit																					(51)
Net income																					268
Total assets			6,322						668						528						7,518
Construction and acquisition expenditures			638						48						—						686

2020			Electric						Gas						Other						Total
Revenues			$1,225						$165						$5						$1,395
Depreciation and amortization			235						19						—						254
Operating income (loss)			285						24						(3)						306
Interest expense																					104
Income tax benefit																					(19)
Net income																					249
Total assets			5,840						647						425						6,912
Construction and acquisition expenditures			483						123						—						606

2019			Electric						Gas						Other						Total
Revenues			$1,283						$191						$2						$1,476
Depreciation and amortization			218						18						—						236
Operating income (loss)			319						31						(3)						347
Interest expense																					102
Income taxes																					49
Net income																					233
Total assets			5,584						535						388						6,507
Construction and acquisition expenditures			475						44						—						519

IPL [Member]

Segment Reporting Information [Line Items]

Segments Of Business

SEGMENTS OF BUSINESS

Alliant Energy - Alliant Energy’s principal businesses as of December 31, 2021 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; 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.”

•ATC Holdings, Non-utility, 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 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.

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):

																											ATC Holdings,
			Utility																								Non-utility,						Alliant Energy
2021			Electric						Gas						Other						Total						Parent and Other						Consolidated
Revenues			$3,081						$456						$49						$3,586						$83						$3,669
Depreciation and amortization			591						54						6						651						6						657
Operating income (loss)			716						63						(11)						768						27						795
Interest expense																					244						33						277
Equity income from unconsolidated investments, net			(2)						—						—						(2)						(60)						(62)
Income tax expense (benefit)																					(87)						13						(74)
Net income attributable to Alliant Energy common shareowners																					618						41						659
Total assets			14,924						1,487						1,103						17,514						1,039						18,553
Investments in equity method subsidiaries			17						—						—						17						491						508
Construction and acquisition expenditures			980						90						—						1,070						99						1,169

																											ATC Holdings,
			Utility																								Non-utility,						Alliant Energy
2020			Electric						Gas						Other						Total						Parent and Other						Consolidated
Revenues			$2,920						$373						$49						$3,342						$74						$3,416
Depreciation and amortization			556						49						5						610						5						615
Operating income (loss)			643						74						(1)						716						24						740
Interest expense																					243						32						275
Equity income from unconsolidated investments, net			(2)						—						—						(2)						(59)						(61)
Income tax expense (benefit)																					(66)						9						(57)
Net income attributable to Alliant Energy common shareowners																					573						41						614
Total assets			14,358						1,413						990						16,761						949						17,710
Investments in equity method subsidiaries			11						—						—						11						465						476
Construction and acquisition expenditures			1,109						182						2						1,293						73						1,366

																											ATC Holdings,
			Utility																								Non-utility,						Alliant Energy
2019			Electric						Gas						Other						Total						Parent and Other						Consolidated
Revenues			$3,064						$455						$46						$3,565						$83						$3,648
Depreciation and amortization			513						47						3						563						4						567
Operating income			679						70						1						750						28						778
Interest expense																					229						44						273
Equity income from unconsolidated investments, net			(1)						—						—						(1)						(52)						(53)
Income tax expense (benefit)																					73						(4)						69
Net income attributable to Alliant Energy common shareowners																					517						40						557
Total assets			13,659						1,269						856						15,784						917						16,701
Investments in equity method subsidiaries			9						—						—						9						449						458
Construction and acquisition expenditures			1,439						100						—						1,539						101						1,640

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):

2021			Electric						Gas						Other						Total
Revenues			$1,752						$265						$46						$2,063
Depreciation and amortization			338						31						6						375
Operating income (loss)			420						43						(3)						460
Interest expense																					139
Income tax benefit																					(36)
Net income available for common stock																					350
Total assets			8,602						819						575						9,996
Construction and acquisition expenditures			342						42						—						384

2020			Electric						Gas						Other						Total
Revenues			$1,695						$208						$44						$1,947
Depreciation and amortization			321						30						5						356
Operating income			358						50						2						410
Interest expense																					139
Income tax benefit																					(47)
Net income available for common stock																					324
Total assets			8,518						766						565						9,849
Construction and acquisition expenditures			626						59						2						687

2019			Electric						Gas						Other						Total
Revenues			$1,781						$264						$44						$2,089
Depreciation and amortization			295						29						3						327
Operating income			360						39						4						403
Interest expense																					127
Income taxes																					24
Net income available for common stock																					284
Total assets			8,075						734						468						9,277
Construction and acquisition expenditures			964						56						—						1,020

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):

2021			Electric						Gas						Other						Total
Revenues			$1,329						$191						$3						$1,523
Depreciation and amortization			253						23						—						276
Operating income (loss)			296						20						(8)						308
Interest expense																					105
Income tax benefit																					(51)
Net income																					268
Total assets			6,322						668						528						7,518
Construction and acquisition expenditures			638						48						—						686

2020			Electric						Gas						Other						Total
Revenues			$1,225						$165						$5						$1,395
Depreciation and amortization			235						19						—						254
Operating income (loss)			285						24						(3)						306
Interest expense																					104
Income tax benefit																					(19)
Net income																					249
Total assets			5,840						647						425						6,912
Construction and acquisition expenditures			483						123						—						606

2019			Electric						Gas						Other						Total
Revenues			$1,283						$191						$2						$1,476
Depreciation and amortization			218						18						—						236
Operating income (loss)			319						31						(3)						347
Interest expense																					102
Income taxes																					49
Net income																					233
Total assets			5,584						535						388						6,507
Construction and acquisition expenditures			475						44						—						519

WPL [Member]

Segment Reporting Information [Line Items]

Segments Of Business

SEGMENTS OF BUSINESS

Alliant Energy - Alliant Energy’s principal businesses as of December 31, 2021 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; 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.”

•ATC Holdings, Non-utility, 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 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.

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):

																											ATC Holdings,
			Utility																								Non-utility,						Alliant Energy
2021			Electric						Gas						Other						Total						Parent and Other						Consolidated
Revenues			$3,081						$456						$49						$3,586						$83						$3,669
Depreciation and amortization			591						54						6						651						6						657
Operating income (loss)			716						63						(11)						768						27						795
Interest expense																					244						33						277
Equity income from unconsolidated investments, net			(2)						—						—						(2)						(60)						(62)
Income tax expense (benefit)																					(87)						13						(74)
Net income attributable to Alliant Energy common shareowners																					618						41						659
Total assets			14,924						1,487						1,103						17,514						1,039						18,553
Investments in equity method subsidiaries			17						—						—						17						491						508
Construction and acquisition expenditures			980						90						—						1,070						99						1,169

																											ATC Holdings,
			Utility																								Non-utility,						Alliant Energy
2020			Electric						Gas						Other						Total						Parent and Other						Consolidated
Revenues			$2,920						$373						$49						$3,342						$74						$3,416
Depreciation and amortization			556						49						5						610						5						615
Operating income (loss)			643						74						(1)						716						24						740
Interest expense																					243						32						275
Equity income from unconsolidated investments, net			(2)						—						—						(2)						(59)						(61)
Income tax expense (benefit)																					(66)						9						(57)
Net income attributable to Alliant Energy common shareowners																					573						41						614
Total assets			14,358						1,413						990						16,761						949						17,710
Investments in equity method subsidiaries			11						—						—						11						465						476
Construction and acquisition expenditures			1,109						182						2						1,293						73						1,366

																											ATC Holdings,
			Utility																								Non-utility,						Alliant Energy
2019			Electric						Gas						Other						Total						Parent and Other						Consolidated
Revenues			$3,064						$455						$46						$3,565						$83						$3,648
Depreciation and amortization			513						47						3						563						4						567
Operating income			679						70						1						750						28						778
Interest expense																					229						44						273
Equity income from unconsolidated investments, net			(1)						—						—						(1)						(52)						(53)
Income tax expense (benefit)																					73						(4)						69
Net income attributable to Alliant Energy common shareowners																					517						40						557
Total assets			13,659						1,269						856						15,784						917						16,701
Investments in equity method subsidiaries			9						—						—						9						449						458
Construction and acquisition expenditures			1,439						100						—						1,539						101						1,640

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):

2021			Electric						Gas						Other						Total
Revenues			$1,752						$265						$46						$2,063
Depreciation and amortization			338						31						6						375
Operating income (loss)			420						43						(3)						460
Interest expense																					139
Income tax benefit																					(36)
Net income available for common stock																					350
Total assets			8,602						819						575						9,996
Construction and acquisition expenditures			342						42						—						384

2020			Electric						Gas						Other						Total
Revenues			$1,695						$208						$44						$1,947
Depreciation and amortization			321						30						5						356
Operating income			358						50						2						410
Interest expense																					139
Income tax benefit																					(47)
Net income available for common stock																					324
Total assets			8,518						766						565						9,849
Construction and acquisition expenditures			626						59						2						687

2019			Electric						Gas						Other						Total
Revenues			$1,781						$264						$44						$2,089
Depreciation and amortization			295						29						3						327
Operating income			360						39						4						403
Interest expense																					127
Income taxes																					24
Net income available for common stock																					284
Total assets			8,075						734						468						9,277
Construction and acquisition expenditures			964						56						—						1,020

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):

2021			Electric						Gas						Other						Total
Revenues			$1,329						$191						$3						$1,523
Depreciation and amortization			253						23						—						276
Operating income (loss)			296						20						(8)						308
Interest expense																					105
Income tax benefit																					(51)
Net income																					268
Total assets			6,322						668						528						7,518
Construction and acquisition expenditures			638						48						—						686

2020			Electric						Gas						Other						Total
Revenues			$1,225						$165						$5						$1,395
Depreciation and amortization			235						19						—						254
Operating income (loss)			285						24						(3)						306
Interest expense																					104
Income tax benefit																					(19)
Net income																					249
Total assets			5,840						647						425						6,912
Construction and acquisition expenditures			483						123						—						606

2019			Electric						Gas						Other						Total
Revenues			$1,283						$191						$2						$1,476
Depreciation and amortization			218						18						—						236
Operating income (loss)			319						31						(3)						347
Interest expense																					102
Income taxes																					49
Net income																					233
Total assets			5,584						535						388						6,507
Construction and acquisition expenditures			475						44						—						519

X

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8924-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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