Disclosure about Fair Value of Financial Instruments - Carrying Amounts and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Financial assets:
Equity securities	$ 1,922
Restricted cash	58,663	$ 475,997
Equity warrants	40,658
Carrying Amount
Financial assets:
Equity securities		4,636
Cash and cash equivalents	303,982	1,545,046
Restricted cash	58,663	475,997
Foreign currency forward contracts, interest rate swaps and cross currency swaps	19,637	4,668
Equity warrants		0
Financial liabilities:
Unsecured credit facility and commercial paper	290,996	0
Senior unsecured notes	11,116,067	11,420,790
Secured debt	2,262,345	2,377,930
Foreign currency forward contracts, interest rate swaps and cross currency swaps	27,731	118,054
Redeemable OP unitholder interests	147,083	116,240
Carrying Amount | Mortgage loans receivable
Financial assets:
Loans receivable	941,357	293,752
Carrying Amount | Other real estate loans receivable
Financial assets:
Loans receivable	174,288	149,620
Carrying Amount | Non-real estate loans receivable
Financial assets:
Loans receivable	210,822	240,269
Fair Value
Financial assets:
Equity securities	1,922	4,636
Cash and cash equivalents	303,982	1,545,046
Restricted cash	58,663	475,997
Foreign currency forward contracts, interest rate swaps and cross currency swaps	19,637	4,668
Equity warrants	40,658	0
Financial liabilities:
Unsecured credit facility and commercial paper	290,996	0
Senior unsecured notes	12,485,436	13,093,926
Secured debt	2,325,322	2,451,782
Foreign currency forward contracts, interest rate swaps and cross currency swaps	27,731	118,054
Redeemable OP unitholder interests	147,083	115,346
Fair Value | Mortgage loans receivable
Financial assets:
Loans receivable	967,813	297,207
Fair Value | Other real estate loans receivable
Financial assets:
Loans receivable	174,088	152,211
Fair Value | Non-real estate loans receivable
Financial assets:
Loans receivable	$ 212,054	$ 255,724