Common Equity (Tables)

12 Months Ended

Dec. 31, 2018

Schedule of Common Equity [Line Items]

Common Stock Activity

A summary of Alliant Energy’s common stock activity was as follows:

	2018		2017		2016
Shares outstanding, January 1	231,348,646		227,673,654		226,918,432
At-the-market offering programs	4,171,013		3,074,931		—
Shareowner Direct Plan issuances	576,965		640,723		732,814
Equity-based compensation plans (Note 13(b))	5,078		5,185		22,408
Other	(38,423	)	(45,847	)	—
Shares outstanding, December 31	236,063,279		231,348,646		227,673,654