Business Segment Information - Segment Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Aug. 31, 2025	Aug. 31, 2024	Aug. 31, 2025	Aug. 31, 2024
Segment Reporting Information [Line Items]
Net sales	$ 2,481.0	$ 2,918.9	$ 4,996.0	$ 5,580.7
Cost of product sold	1,171.0	1,407.1	2,419.4	2,665.1
Comparable operating income (loss)	874.0	(1,229.4)	1,587.8	(287.8)
Income (loss) from unconsolidated investments	(3.5)	(1.2)	(7.0)	80.8
Interest expense, net	(87.6)	(104.0)	(186.5)	(206.8)
Income (loss) before income taxes	782.9	(1,334.6)	1,394.3	(413.8)
Capital expenditures	217.3	327.8	410.1	703.1
Depreciation and amortization	103.1	109.6	208.6	221.5
Income (loss) from unconsolidated investments
Equity in earnings (losses) of equity method investees and related activities	3.0	3.4	(0.5)	2.1
Net gain (loss) on conversion and exchange to exchangeable shares	0.0	0.0	0.0	83.3
Impairment of equity method investments	(1.5)	(2.1)	(1.5)	(2.1)
Unrealized net gain (loss) on securities measured at fair value	(5.0)	(2.5)	(5.0)	(2.5)
Income (loss) from unconsolidated investments	(3.5)	(1.2)	(7.0)	80.8
Interest expense	(89.0)	(105.8)	(189.6)	(210.6)
Interest income	2.4	1.8	4.1	3.8
Loss on extinguishment of debt	(1.0)	0.0	(1.0)	0.0
Comparable Adjustments
Segment Reporting Information [Line Items]
Cost of product sold	(15.2)	18.6	1.3	(3.4)
Comparable operating income (loss)	886.2	1,089.8	1,696.1	2,013.8
Comparable adjustments	(12.2)	(2,319.2)	(108.3)	(2,301.6)
Operating Segments | Beer
Segment Reporting Information [Line Items]
Net sales	2,345.0	2,530.2	4,579.5	4,803.0
Cost of product sold	(1,105.0)	(1,163.8)	(2,152.5)	(2,223.5)
Marketing	$ (190.7)	$ (193.5)	$ (391.2)	$ (383.8)
Marketing as a percentage of net sales	8.10%	7.60%	8.50%	8.00%
General and administrative expenses	$ (97.7)	$ (95.2)	$ (210.8)	$ (195.0)
Comparable operating income (loss)	$ 951.6	$ 1,077.7	$ 1,825.0	$ 2,000.7
Operating margin	40.60%	42.60%	39.90%	41.70%
Capital expenditures	$ 197.0	$ 257.2	$ 370.2	$ 571.6
Depreciation and amortization	$ 82.6	$ 82.5	$ 159.4	$ 168.9
Depreciation and amortization as a percentage of net sales	3.50%	3.30%	3.50%	3.50%
Operating Segments | Wine and Spirits
Segment Reporting Information [Line Items]
Net sales	$ 136.0	$ 388.7	$ 416.5	$ 777.7
Cost of product sold	(81.2)	(224.7)	(265.6)	(445.0)
Marketing	$ (20.0)	$ (36.0)	$ (54.9)	$ (76.9)
Marketing as a percentage of net sales	14.70%	9.30%	13.20%	9.90%
General and administrative expenses	$ (54.6)	$ (57.5)	$ (121.8)	$ (125.6)
Comparable operating income (loss)	$ (19.8)	$ 70.5	$ (25.8)	$ 130.2
Operating margin	(14.60%)	18.10%	(6.20%)	16.70%
Capital expenditures	$ 19.5	$ 41.0	$ 37.5	$ 90.6
Depreciation and amortization	$ 14.3	$ 21.5	$ 36.5	$ 42.8
Depreciation and amortization as a percentage of net sales	10.50%	5.50%	8.80%	5.50%
Operating Segments | Corporate Operations and Other
Segment Reporting Information [Line Items]
Net sales	$ 0.0	$ 0.0	$ 0.0	$ 0.0
Cost of product sold	0.0	0.0	0.0	0.0
Marketing	0.0	0.0	0.0	0.0
General and administrative expenses	(45.6)	(58.4)	(103.1)	(117.1)
Comparable operating income (loss)	(45.6)	(58.4)	(103.1)	(117.1)
Capital expenditures	0.8	29.6	2.4	40.9
Depreciation and amortization	$ 6.2	$ 5.6	$ 12.7	$ 9.8