Common Equity (Tables)

9 Months Ended

Sep. 30, 2015

Stockholders' Equity Note [Abstract]

Common Share Activity

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

Shares outstanding, January 1, 2015	110,935,680
At-the-market offering program	2,186,617
Shareowner Direct Plan	204,213
Equity-based compensation plans (Note 9(b))	56,378
Other	(22,463	)
Shares outstanding, September 30, 2015	113,360,425