Shareholders' Equity (Narrative) (Details)		3 Months Ended		6 Months Ended
	Jan. 13, 2022 USD ($) $ / shares shares	Jun. 30, 2022 USD ($) $ / shares	Jun. 30, 2021 USD ($) $ / shares	Jun. 30, 2022 USD ($) dividend boardMember $ / shares	Jun. 30, 2021 USD ($) $ / shares	Dec. 31, 2021 USD ($)
Class of Stock [Line Items]
Number of quarterly dividends in arrearage before preferred shareholders can elect additional board members | dividend				6
Number of additional board members the preferred shareholders can elect in the case of an excess arrearage of quarterly dividends | boardMember				2
Amount of preferred dividends in arrears				$ 0
Affirmative vote of outstanding shares of a series of Preferred Shares required for any material and adverse amendment to the terms of series, percent				66.67%
Affirmative vote of outstanding shares of all Preferred Shares, voting as a single class, required to issue shares ranking senior to Preferred Shares, percent				66.67%
Redemption price per share (in USD per share) | $ / shares		$ 25.00		$ 25.00
Liquidation Preference		$ 4,350,000,000		$ 4,350,000,000		$ 4,100,000,000
Common stock dividends paid in aggregate		$ 351,300,000	$ 350,100,000	$ 702,500,000	$ 700,200,000
Distributions to common shareholders and restricted share unitholders (in USD per share) | $ / shares		$ 2.00	$ 2.00	$ 4.00	$ 4.00
Preferred share dividends		$ 48,673,000	$ 46,183,000	$ 97,038,000	$ 92,263,000
Series S Preferred Stock
Class of Stock [Line Items]
Stock issued during period (in shares) | shares	10,000,000
Preferred shares per depositary share (in shares) | shares	0.001
Dividend rate percentage	4.10%			4.10%
Shares issued (in USD per share) | $ / shares	$ 25.00
Liquidation Preference	$ 250,000,000	$ 250,000,000		$ 250,000,000		$ 0
Issuance costs	$ 7,200,000