Investments (Tables)

12 Months Ended

Dec. 31, 2020

Investment [Line Items]

Unconsolidated Equity Investments

Alliant Energy’s unconsolidated investments accounted for under the equity method of accounting are as follows (in millions):

	Ownership Interest at	Carrying Value at December 31,		Equity (Income) / Loss
	December 31, 2020	2020	2019	2020	2019	2018
ATC Holdings	16%, 20%	$331	$320	($47)	($45)	($38)
Non-utility wind farm in Oklahoma	50%	103	105	(8)	(5)	(16)
Other	Various	42	33	(6)	(3)	(1)
		$476	$458	($61)	($53)	($55)

Summary Financial Information

Summary aggregate financial information from the financial statements of these holdings is as follows (in millions):

	Alliant Energy
	2020	2019	2018
Revenues	$801	$783	$724
Operating income	376	359	325
Net income	343	340	217
As of December 31:
Current assets	121	139
Non-current assets	6,388	5,964
Current liabilities	317	507
Non-current liabilities	2,997	2,659
Noncontrolling interest	192	208