Subsequent Events (Details)	Oct. 28, 2021 USD ($) $ / shares shares	Sep. 30, 2021 USD ($) $ / shares	Dec. 31, 2020 USD ($) $ / shares
Subsequent Event [Line Items]
Preferred stock, par value, in usd per share		$ 0.001	$ 0.001
Long-term debt | $		$ 1,925,000,000	$ 844,000,000
Subsequent Event | Senior Notes | 1.800% Senior Notes Due October 2026
Subsequent Event [Line Items]
Long-term debt | $	$ 650,000,000
Interest rate on senior notes	1.80%
Subsequent Event | Series D Preferred Stock
Subsequent Event [Line Items]
Preferred stock, depository share ownership interest	0.01
Preferred stock, depositary shares issued | shares	1,000,000
Preferred stock, par value, in usd per share	$ 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, dividend rate, percentage	4.25%
Preferred stock, period dividend rate reset using the five-year treasury rate	5 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	3.074%
Subsequent Event | Series E Preferred Stock
Subsequent Event [Line Items]
Preferred stock, depository share ownership interest	0.01
Preferred stock, depositary shares issued | shares	600,000
Preferred stock, par value, in usd per share	$ 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, dividend rate, percentage	4.70%
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%