Shareholders' Equity - Preferred shares (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		1 Months Ended				4 Months Ended
	Jan. 01, 2018	Sep. 30, 2021	Jun. 30, 2021	Nov. 30, 2017	Aug. 31, 2017	Nov. 30, 2017	Dec. 31, 2022	Jun. 30, 2022
Class of Stock [Line Items]
Preferred shares, par value per share							$ 0.01
Series C Preferred Shares
Class of Stock [Line Items]
Preferred shares, dividend rate (as a percent)	6.75%
Series E preferred shares
Class of Stock [Line Items]
Preferred shares, dividend rate (as a percent)		5.25%
Preferred shares, redemption price per share		$ 25
Series F Preferred Shares
Class of Stock [Line Items]
Preferred shares issued				$ 100	$ 230	$ 330
Preferred shares, dividend rate (as a percent)						5.45%
Preferred shares, par value per share				$ 0.01		$ 0.01
Liquidation preference per share				25,000		25,000
Preferred shares, redemption price per share				$ 25,000		$ 25,000
Series F depositary share equivalent
Class of Stock [Line Items]
Preference shares, number of shares issued				13.2		13.2
Proportionate interest of preference shares, per depositary share				0.10%		0.10%
Liquidation preference per share				$ 25		$ 25
Preferred shares, redemption price per share				$ 25		$ 25
Series G Preferred Stock
Class of Stock [Line Items]
Preferred shares issued			$ 500
Preferred shares, dividend rate (as a percent)			4.55%
Preferred shares, par value per share			$ 0.01
Liquidation preference per share			25,000
Preferred shares, redemption price per share			$ 25,000
Series G depositary share equivalent
Class of Stock [Line Items]
Preference shares, number of shares issued			20.0
Proportionate interest of preference shares, per depositary share								0.10%
Liquidation preference per share			$ 25
Preferred shares, redemption price per share			$ 25