Stockholders' Equity and EPS - Preferred Stock (Details)				6 Months Ended
	May 13, 2021 $ / shares shares	Feb. 02, 2021 $ / shares shares	Dec. 09, 2019 $ / shares shares	Jun. 30, 2021 $ / shares	Dec. 31, 2020 $ / shares
Class of Stock [Line Items]
Preferred stock, par value, in usd per share				$ 0.001	$ 0.001
Preferred Stock, Series A
Class of Stock [Line Items]
Preferred stock, dividend rate, percentage			5.25%
Preferred stock, depositary shares issued | shares			14,000,000
Preferred stock, depository share ownership interest				0.025
Preferred stock, par value, in usd per share			$ 0.001	$ 0.001
Preferred stock, liquidation preference per share, in usd per share			1,000
Preferred stock, liquidation preference per depositary share			$ 25
Series B Preferred Stock
Class of Stock [Line Items]
Preferred stock, dividend rate, percentage		4.10%
Preferred stock, depositary shares issued | shares		750,000
Preferred stock, depository share ownership interest				0.01
Preferred stock, par value, in usd per share		$ 0.001		$ 0.001
Preferred stock, liquidation preference per share, in usd per share		100,000
Preferred stock, liquidation preference per depositary share		$ 1,000
Preferred stock, period dividend rate reset using the ten-year treasury rate		10 years
Preferred stock, number of business days prior to each reset date dividend rate calculated		3 days
Preferred stock, number of days used for average yields on actively traded US Treasury securities		5 days
Preferred stock, margin used for dividend rate at reset		3.064%
Series C Preferred Stock
Class of Stock [Line Items]
Preferred stock, dividend rate, percentage	4.00%
Preferred stock, depositary shares issued | shares	1,000,000
Preferred stock, depository share ownership interest				0.01
Preferred stock, par value, in usd per share	$ 0.001			$ 0.001
Preferred stock, liquidation preference per share, in usd per share	100,000
Preferred stock, liquidation preference per depositary share	$ 1,000	$ 1,000
Preferred stock, number of business days prior to each reset date dividend rate calculated		3 days
Preferred stock, number of days used for average yields on actively traded US Treasury securities	5 days
Preferred stock, period dividend rate reset using the five-year treasury rate	5 years
Preferred stock, margin used for dividend rate at reset	3.202%