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Common Equity - Additional Information (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		3 Months Ended
	Oct. 26, 2026	Sep. 30, 2026	Jun. 30, 2026	Mar. 31, 2026	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Jan. 31, 2026	Dec. 31, 2025
Class of Stock
Anti-dilutive share-based awards and options excluded from computation of diluted earnings per share		0.0			0.0
Stock repurchase program - amount authorized								$ 150.0
Treasury stock, value		$ 116.2							$ 111.0
Repurchase Program 2026
Class of Stock
Treasury stock, value		$ 5.2
Class A Common Shares
Class of Stock
Dividends declared per share		$ 0.1	$ 0.1	$ 0.1	$ 0.095	$ 0.095	$ 0.095
Class A Common Shares \| O 2026 Q4 Dividends \| Subsequent Event
Class of Stock
Dividends declared per share	$ 0.10
Class B Common Stock
Class of Stock
Dividends declared per share		$ 0.1	$ 0.1	$ 0.1	$ 0.095	$ 0.095	$ 0.095
Class B Common Stock \| O 2026 Q4 Dividends \| Subsequent Event
Class of Stock
Dividends declared per share	$ 0.10