Revenues (Tables)

12 Months Ended

Dec. 31, 2019

Disaggregation of Revenue [Line Items]

Disaggregation of Revenues

Disaggregation of revenues from contracts with customers, which correlates to revenues for each reportable segment, was as follows (in millions):

	Alliant Energy						IPL						WPL
	2019		2018		2017		2019		2018		2017		2019		2018		2017
Electric Utility:
Retail - residential		$1,092.4		$1,063.4		$1,006.2		$601.5		$590.6		$535.6		$490.9		$472.8		$470.6
Retail - commercial	769.7		735.6		710.3		510.3		486.8		452.7		259.4		248.8		257.6
Retail - industrial	889.1		888.8		853.1		503.9		500.8		459.7		385.2		388.0		393.4
Wholesale	176.4		188.4		238.4		63.5		71.2		95.5		112.9		117.2		142.9
Bulk power and other	136.0		124.1		86.7		102.0		81.7		55.4		34.0		42.4		31.3
Total Electric Utility	3,063.6		3,000.3		2,894.7		1,781.2		1,731.1		1,598.9		1,282.4		1,269.2		1,295.8
Gas Utility:
Retail - residential	259.4		254.4		224.7		149.3		152.3		123.2		110.1		102.1		101.5
Retail - commercial	133.0		133.0		123.2		74.9		75.9		67.9		58.1		57.1		55.3
Retail - industrial	16.0		14.9		16.7		11.7		10.2		11.1		4.3		4.7		5.6
Transportation/other	46.8		44.3		36.3		28.3		27.8		23.8		18.5		16.5		12.5
Total Gas Utility	455.2		446.6		400.9		264.2		266.2		226.0		191.0		180.4		174.9
Other Utility:
Steam	37.2		35.2		34.6		37.2		35.2		34.6		—		—		—
Other utility	9.3		12.8		12.9		7.0		9.8		10.8		2.3		3.0		2.1
Total Other Utility	46.5		48.0		47.5		44.2		45.0		45.4		2.3		3.0		2.1
Non-Utility and Other:
Transportation and other	82.4		39.6		39.1		—		—		—		—		—		—
Total Non-Utility and Other	82.4		39.6		39.1		—		—		—		—		—		—
Total revenues		$3,647.7		$3,534.5		$3,382.2		$2,089.6		$2,042.3		$1,870.3		$1,475.7		$1,452.6		$1,472.8

IPL [Member]

Disaggregation of Revenue [Line Items]

Disaggregation of Revenues

Disaggregation of revenues from contracts with customers, which correlates to revenues for each reportable segment, was as follows (in millions):

	Alliant Energy						IPL						WPL
	2019		2018		2017		2019		2018		2017		2019		2018		2017
Electric Utility:
Retail - residential		$1,092.4		$1,063.4		$1,006.2		$601.5		$590.6		$535.6		$490.9		$472.8		$470.6
Retail - commercial	769.7		735.6		710.3		510.3		486.8		452.7		259.4		248.8		257.6
Retail - industrial	889.1		888.8		853.1		503.9		500.8		459.7		385.2		388.0		393.4
Wholesale	176.4		188.4		238.4		63.5		71.2		95.5		112.9		117.2		142.9
Bulk power and other	136.0		124.1		86.7		102.0		81.7		55.4		34.0		42.4		31.3
Total Electric Utility	3,063.6		3,000.3		2,894.7		1,781.2		1,731.1		1,598.9		1,282.4		1,269.2		1,295.8
Gas Utility:
Retail - residential	259.4		254.4		224.7		149.3		152.3		123.2		110.1		102.1		101.5
Retail - commercial	133.0		133.0		123.2		74.9		75.9		67.9		58.1		57.1		55.3
Retail - industrial	16.0		14.9		16.7		11.7		10.2		11.1		4.3		4.7		5.6
Transportation/other	46.8		44.3		36.3		28.3		27.8		23.8		18.5		16.5		12.5
Total Gas Utility	455.2		446.6		400.9		264.2		266.2		226.0		191.0		180.4		174.9
Other Utility:
Steam	37.2		35.2		34.6		37.2		35.2		34.6		—		—		—
Other utility	9.3		12.8		12.9		7.0		9.8		10.8		2.3		3.0		2.1
Total Other Utility	46.5		48.0		47.5		44.2		45.0		45.4		2.3		3.0		2.1
Non-Utility and Other:
Transportation and other	82.4		39.6		39.1		—		—		—		—		—		—
Total Non-Utility and Other	82.4		39.6		39.1		—		—		—		—		—		—
Total revenues		$3,647.7		$3,534.5		$3,382.2		$2,089.6		$2,042.3		$1,870.3		$1,475.7		$1,452.6		$1,472.8

WPL [Member]

Disaggregation of Revenue [Line Items]

Disaggregation of Revenues

Disaggregation of revenues from contracts with customers, which correlates to revenues for each reportable segment, was as follows (in millions):

	Alliant Energy						IPL						WPL
	2019		2018		2017		2019		2018		2017		2019		2018		2017
Electric Utility:
Retail - residential		$1,092.4		$1,063.4		$1,006.2		$601.5		$590.6		$535.6		$490.9		$472.8		$470.6
Retail - commercial	769.7		735.6		710.3		510.3		486.8		452.7		259.4		248.8		257.6
Retail - industrial	889.1		888.8		853.1		503.9		500.8		459.7		385.2		388.0		393.4
Wholesale	176.4		188.4		238.4		63.5		71.2		95.5		112.9		117.2		142.9
Bulk power and other	136.0		124.1		86.7		102.0		81.7		55.4		34.0		42.4		31.3
Total Electric Utility	3,063.6		3,000.3		2,894.7		1,781.2		1,731.1		1,598.9		1,282.4		1,269.2		1,295.8
Gas Utility:
Retail - residential	259.4		254.4		224.7		149.3		152.3		123.2		110.1		102.1		101.5
Retail - commercial	133.0		133.0		123.2		74.9		75.9		67.9		58.1		57.1		55.3
Retail - industrial	16.0		14.9		16.7		11.7		10.2		11.1		4.3		4.7		5.6
Transportation/other	46.8		44.3		36.3		28.3		27.8		23.8		18.5		16.5		12.5
Total Gas Utility	455.2		446.6		400.9		264.2		266.2		226.0		191.0		180.4		174.9
Other Utility:
Steam	37.2		35.2		34.6		37.2		35.2		34.6		—		—		—
Other utility	9.3		12.8		12.9		7.0		9.8		10.8		2.3		3.0		2.1
Total Other Utility	46.5		48.0		47.5		44.2		45.0		45.4		2.3		3.0		2.1
Non-Utility and Other:
Transportation and other	82.4		39.6		39.1		—		—		—		—		—		—
Total Non-Utility and Other	82.4		39.6		39.1		—		—		—		—		—		—
Total revenues		$3,647.7		$3,534.5		$3,382.2		$2,089.6		$2,042.3		$1,870.3		$1,475.7		$1,452.6		$1,472.8