Dividends (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Jan. 14, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Class of Stock [Line Items]
Dividends		$ 367,291	$ 356,409	$ 333,692
Dividends Payable, Date Declared		Jan. 14, 2022
Dividends Payable, Date of Record		Jan. 31, 2022
Dividends Payable, Date to be Paid		Feb. 15, 2022
Dividends, Per share (in dollars per share)		$ 2.100000	$ 2.070000	$ 2.030000
Common stock dividends declared and paid (in dollars per share)		$ 2.1000	$ 2.0700	$ 2.0300
Subsequent Event
Class of Stock [Line Items]
Common stock dividends declared and paid (in dollars per share)	$ 0.530
Series F Preferred Stock
Class of Stock [Line Items]
Preferred stock, dividends		$ 14,999	$ 17,940	$ 17,940
Preferred stock dividends declared and paid (in dollars per share)		$ 1.086944	$ 1.3000	$ 1.3000
Series E Preferred Stock
Class of Stock [Line Items]
Preferred stock, dividends		$ 0	$ 0	$ 13,201
Preferred stock dividends declared and paid (in dollars per share)				$ 1.147917
Ordinary dividends
Class of Stock [Line Items]
Dividends, Per share (in dollars per share)		$ 1.615753	$ 1.659755	1.762899
Nontaxable distributions
Class of Stock [Line Items]
Dividends, Per share (in dollars per share)		$ 0.484247	$ 0.410245	$ 0.267101