v3.26.1

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2026	Dec. 31, 2025
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	480,000,000	480,000,000
Common stock, shares outstanding (in shares)	258,277,037	257,137,261
Shares in deferred compensation trust (in shares)	343,622	367,338
Shares in deferred compensation trust, weighted average cost per share (in dollars per share)	$ 39.73	$ 39.05
IPL [Member]
Common stock, par value (in dollars per share)	$ 2.50	$ 2.50
Common stock, shares authorized (in shares)	24,000,000	24,000,000
Common stock, shares outstanding (in shares)	13,370,788	13,370,788
WPL [Member]
Common stock, par value (in dollars per share)	$ 5	$ 5
Common stock, shares authorized (in shares)	18,000,000	18,000,000
Common stock, shares outstanding (in shares)	13,236,601	13,236,601

Total number of common stock shares held in trust.

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ALLIANT ENERGY CORP 10-Q