Supplemental Cash Flow Information (Detail) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Operating lease liabilities	$ 46.9	$ 30.4
Income taxes	1,350.5	358.8
Interest	138.0	125.6
Operating lease liabilities	42.7	42.5
Cash and Cash Equivalents
Open reverse repurchase commitments	81.3	68.0	$ 68.2
Common equities \| Quarterly dividend
Common share dividends	$ 58.6	$ 58.5

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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