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Fair Value of Assets and Liabilities - Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Sep. 30, 2021	Aug. 31, 2021	May 31, 2021	Dec. 31, 2020
Fair Value of Financial Instruments
Senior notes	$ 2,479,772				$ 2,033,242
Mortgage notes payable	98,178				169,729
Unamortized debt premiums, discounts and issuance	32,351				39,871
Carrying Amount
Fair Value of Financial Instruments
Fair value of debt	2,577,950				2,202,971
Carrying Amount \| Mortgage Note Payable
Fair Value of Financial Instruments
Mortgage notes payable	98,178				169,729
Fair Value
Fair Value of Financial Instruments
Fair value of debt	2,661,462				2,335,352
Fair Value \| Mortgage Note Payable
Fair Value of Financial Instruments
Mortgage notes payable	100,294				174,952
Senior Notes and Mortgages
Fair Value of Financial Instruments
Unamortized debt premiums, discounts and issuance	$ 32,351				39,871
Senior Unsecured Notes \| Senior unsecured notes, 4.150% interest rate, due in 2022
Fair Value of Financial Instruments
Interest rate (as a percent)	4.15%	4.15%
Senior Unsecured Notes \| Senior unsecured notes, 4.00% interest rate, due in 2022
Fair Value of Financial Instruments
Interest rate (as a percent)	4.00%
Senior Unsecured Notes \| Senior unsecured notes, 4.25% interest rate, due in 2024
Fair Value of Financial Instruments
Interest rate (as a percent)	4.25%
Senior Unsecured Notes \| Senior unsecured notes, 4.50% interest rate, due in 2025
Fair Value of Financial Instruments
Interest rate (as a percent)	4.50%
Senior Unsecured Notes \| Senior unsecured notes, 2.650% interest rate, due in 2026
Fair Value of Financial Instruments
Interest rate (as a percent)	2.65%			2.65%
Senior Unsecured Notes \| Senior unsecured notes, 2.400% interest rate, due in 2027
Fair Value of Financial Instruments
Interest rate (as a percent)	2.40%		2.40%
Senior Unsecured Notes \| Senior unsecured notes, 3.450% interest rate, due in 2031
Fair Value of Financial Instruments
Interest rate (as a percent)	3.45%	3.45%
Senior Unsecured Notes \| Senior unsecured notes, 5.875% interest rate, due in 2046
Fair Value of Financial Instruments
Interest rate (as a percent)	5.875%
Senior Unsecured Notes \| Carrying Amount \| Senior unsecured notes, 4.150% interest rate, due in 2022
Fair Value of Financial Instruments
Senior notes	$ 0				298,853
Senior Unsecured Notes \| Carrying Amount \| Senior unsecured notes, 4.00% interest rate, due in 2022
Fair Value of Financial Instruments
Senior notes	299,500				298,579
Senior Unsecured Notes \| Carrying Amount \| Senior unsecured notes, 4.25% interest rate, due in 2024
Fair Value of Financial Instruments
Senior notes	344,581				342,299
Senior Unsecured Notes \| Carrying Amount \| Senior unsecured notes, 4.50% interest rate, due in 2025
Fair Value of Financial Instruments
Senior notes	639,370				635,921
Senior Unsecured Notes \| Carrying Amount \| Senior unsecured notes, 2.650% interest rate, due in 2026
Fair Value of Financial Instruments
Senior notes	297,213				0
Senior Unsecured Notes \| Carrying Amount \| Senior unsecured notes, 2.400% interest rate, due in 2027
Fair Value of Financial Instruments
Senior notes	346,845				0
Senior Unsecured Notes \| Carrying Amount \| Senior unsecured notes, 3.450% interest rate, due in 2031
Fair Value of Financial Instruments
Senior notes	395,744				0
Senior Unsecured Notes \| Carrying Amount \| Senior unsecured notes, 5.875% interest rate, due in 2046
Fair Value of Financial Instruments
Senior notes	0				301,264
Senior Unsecured Notes \| Carrying Amount \| Senior unsecured notes, 6.375% interest rate, due in 2050
Fair Value of Financial Instruments
Senior notes	156,519				156,326
Senior Unsecured Notes \| Fair Value \| Senior unsecured notes, 4.150% interest rate, due in 2022
Fair Value of Financial Instruments
Senior notes	0				306,192
Senior Unsecured Notes \| Fair Value \| Senior unsecured notes, 4.00% interest rate, due in 2022
Fair Value of Financial Instruments
Senior notes	304,148				306,756
Senior Unsecured Notes \| Fair Value \| Senior unsecured notes, 4.25% interest rate, due in 2024
Fair Value of Financial Instruments
Senior notes	365,449				365,435
Senior Unsecured Notes \| Fair Value \| Senior unsecured notes, 4.50% interest rate, due in 2025
Fair Value of Financial Instruments
Senior notes	687,749				688,399
Senior Unsecured Notes \| Fair Value \| Senior unsecured notes, 2.650% interest rate, due in 2026
Fair Value of Financial Instruments
Senior notes	298,502				0
Senior Unsecured Notes \| Fair Value \| Senior unsecured notes, 2.400% interest rate, due in 2027
Fair Value of Financial Instruments
Senior notes	339,764				0
Senior Unsecured Notes \| Fair Value \| Senior unsecured notes, 3.450% interest rate, due in 2031
Fair Value of Financial Instruments
Senior notes	388,458				0
Senior Unsecured Notes \| Fair Value \| Senior unsecured notes, 5.875% interest rate, due in 2046
Fair Value of Financial Instruments
Senior notes	0				322,028
Senior Unsecured Notes \| Fair Value \| Senior unsecured notes, 6.375% interest rate, due in 2050
Fair Value of Financial Instruments
Senior notes	$ 177,098				$ 171,590