Income Taxes - Taxable Characteristics of Distributions Paid (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Dividends distributed, amount	$ 682,845	$ 654,358	$ 542,267
Total dividends distributed, amount	685,899	657,460	544,740
Series L Preferred Stock [Member]
Ordinary income, amount	$ 7,755	$ 11,432	$ 9,657
Ordinary income, percent	68.00%	100.00%	84.00%
Capital gain, amount	$ 3,650		$ 1,839
Capital gain, percent	32.00%		16.00%
Dividends distributed, amount	$ 11,405	$ 11,432	$ 11,496
Dividends distributed, percent	100.00%	100.00%	100.00%
Series M Preferred Stock [Member]
Ordinary income, amount	$ 9,340	$ 13,749	$ 11,615
Ordinary income, percent	68.00%	100.00%	84.00%
Capital gain, amount	$ 4,396		$ 2,212
Capital gain, percent	32.00%		16.00%
Dividends distributed, amount	$ 13,736	$ 13,749	$ 13,827
Dividends distributed, percent	100.00%	100.00%	100.00%
Series N Preferred Stock [Member]
Ordinary income, amount	$ 3,766
Ordinary income, percent	68.00%
Capital gain, amount	$ 1,772
Capital gain, percent	32.00%
Dividends distributed, amount	$ 5,538
Dividends distributed, percent	100.00%
Common Stock 1 [Member]
Ordinary income, amount	$ 443,473	$ 622,885	$ 418,725
Ordinary income, percent	68.00%	99.00%	81.00%
Capital gain, amount	$ 208,693		$ 82,711
Capital gain, percent	32.00%		16.00%
Dividends distributed, amount	$ 652,166	$ 629,177	$ 516,944
Dividends distributed, percent	100.00%	100.00%	100.00%
Return of capital, amount		$ 6,292	$ 15,508
Return of capital, percent		1.00%	3.00%