CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (Unaudited) - USD ($) $ in Millions	Total	Total	Common shares and paid-in surplus	Retained earnings	AOCI, after tax	Non-controlling interest	Total Equity	BAM Non-controlling interest	BAM Total Equity
Beginning Balances at Dec. 31, 2019		$ 3,261.5	$ 596.3	$ 2,672.4	$ (7.2)	$ (116.8)	$ 3,144.7
Increase (Decrease) in Shareholders' Equity
Net (loss) income	$ 190.0	219.5		219.5		(29.5)	190.0
Net change in foreign currency translation and other		0.7			0.7	0.3	1.0
Comprehensive (loss) income	220.5	220.2		219.5	0.7	(29.2)	191.0
Dividends declared on common shares		(3.2)		(3.2)			(3.2)
Dividends to non-controlling interests						(2.3)	(2.3)
Issuances of common shares		1.5	1.5				1.5
Repurchases and retirements of common shares		(85.2)	(18.6)	(66.6)			(85.2)
BAM member surplus contribution, net of tax								$ 46.9	$ 46.9
Amortization of restricted share awards		12.3	12.3				12.3
Recognition of equity-based compensation expense of subsidiaries	1.0	1.0	1.0
Net contributions and dilution from other non-controlling interests		(0.4)	(0.4)			2.1	1.7
Acquisition of non-controlling interests						0.8	0.8
Ending Balances at Sep. 30, 2020		3,407.7	592.1	2,822.1	(6.5)	(98.5)	3,309.2
Beginning Balances at Jun. 30, 2020		3,166.0	587.0	2,589.3	(10.3)	(102.7)	3,063.3
Increase (Decrease) in Shareholders' Equity
Net (loss) income	222.0	232.9		232.9		(10.9)	222.0
Net change in foreign currency translation and other		3.8			3.8	0.2	4.0
Comprehensive (loss) income	236.8	236.7		232.9	3.8	(10.7)	226.0
Dividends to non-controlling interests						(0.9)	(0.9)
Issuances of common shares		0.2	0.2				0.2
Repurchases and retirements of common shares		(0.1)		(0.1)			(0.1)
BAM member surplus contribution, net of tax								15.4	15.4
Amortization of restricted share awards		3.6	3.6				3.6
Recognition of equity-based compensation expense of subsidiaries		1.0	1.0				1.0
Net contributions and dilution from other non-controlling interests		0.3	0.3			(0.4)	(0.1)
Acquisition of non-controlling interests	0.8					0.8
Ending Balances at Sep. 30, 2020		3,407.7	592.1	2,822.1	(6.5)	(98.5)	3,309.2
Beginning Balances at Dec. 31, 2020	3,817.9	3,906.0	595.2	3,311.2	(0.4)	(88.1)	3,817.9
Increase (Decrease) in Shareholders' Equity
Net (loss) income	(361.9)	(308.2)		(308.2)		(53.7)	(361.9)
Net change in foreign currency translation and other		0.4			0.4		0.4
Comprehensive (loss) income	(307.6)	(307.8)		(308.2)	0.4	(53.7)	(361.5)
Dividends declared on common shares		(3.1)		(3.1)			(3.1)
Dividends to non-controlling interests						(1.8)	(1.8)
Issuances of common shares		1.7	1.7				1.7
Issuances of shares of non-controlling interests						6.1	6.1
Repurchases and retirements of common shares		(94.6)	(16.6)	(78.0)			(94.6)
BAM member surplus contribution, net of tax								44.8	44.8
Amortization of restricted share awards		11.1	11.1				11.1
Recognition of equity-based compensation expense of subsidiaries		2.0	2.0			0.3	2.3
Net contributions and dilution from other non-controlling interests		6.4	(7.2)	13.4	0.2	(5.3)	1.1
Acquisition of non-controlling interests						230.3	230.3
Ending Balances at Sep. 30, 2021	3,654.3	3,521.7	586.2	2,935.3	0.2	132.6	3,654.3
Beginning Balances at Jun. 30, 2021		3,978.2	597.2	3,378.6	2.4	129.8	4,108.0
Increase (Decrease) in Shareholders' Equity
Net (loss) income	(383.9)	(371.4)		(371.4)		(12.5)	(383.9)
Net change in foreign currency translation and other		(2.2)			(2.2)	(0.2)	(2.4)
Comprehensive (loss) income	(373.6)	(373.6)		(371.4)	(2.2)	(12.7)	(386.3)
Dividends to non-controlling interests						(0.6)	(0.6)
Repurchases and retirements of common shares		(87.1)	(15.2)	(71.9)			(87.1)
BAM member surplus contribution, net of tax								$ 14.7	$ 14.7
Amortization of restricted share awards		3.6	3.6				3.6
Recognition of equity-based compensation expense of subsidiaries		0.2	0.2				0.2
Net contributions and dilution from other non-controlling interests		0.4	0.4			1.4	1.8
Ending Balances at Sep. 30, 2021	$ 3,654.3	$ 3,521.7	$ 586.2	$ 2,935.3	$ 0.2	$ 132.6	$ 3,654.3