Common Stock and Related Matters - Dividends Declared And Or Paid (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Dividends Payable [Line Items]
Accrued preferred dividends payable date				Aug. 14, 2020
Dividends Declared per Share of Common Stock		$ 0.10	$ 0.91	$ 1.01	$ 1.82
Dividend Declared, Q2 2020 [Member]
Dividends Payable [Line Items]
Accrued preferred dividends payable date				Aug. 17, 2020
Total Common Dividends Declared				$ 23.7
Amount of Common Dividends Paid or To Be Paid				23.3
Accrued Dividends	[1]	$ 0.4		$ 0.4
Dividends Declared per Share of Common Stock				$ 0.10000
Dividend Declared, Q1 2020 [Member]
Dividends Payable [Line Items]
Accrued preferred dividends payable date				May 15, 2020
Total Common Dividends Declared				$ 23.7
Amount of Common Dividends Paid or To Be Paid				23.3
Accrued Dividends	[1]	0.4		$ 0.4
Dividends Declared per Share of Common Stock				$ 0.10000
Dividend Declared, Q4 2019 [Member]
Dividends Payable [Line Items]
Accrued preferred dividends payable date				Feb. 18, 2020
Total Common Dividends Declared				$ 216.0
Amount of Common Dividends Paid or To Be Paid				212.0
Accrued Dividends	[1]	$ 4.0		$ 4.0
Dividends Declared per Share of Common Stock				$ 0.91000

[1] Represents accrued dividends on restricted stock and restricted stock units that are payable upon vesting.