Disclosure about Fair Value of Financial Instruments - Carrying Amounts and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Financial assets:
Equity securities	$ 3,061
Restricted cash	295,102	$ 475,997	[1]
Equity warrants	32,419
Carrying Amount
Financial assets:
Equity securities		4,636
Cash and cash equivalents	513,602	1,545,046
Restricted cash	295,102	475,997
Foreign currency forward contracts, interest rate swaps and cross currency swaps	6,256	4,668
Equity warrants		0
Financial liabilities:
Senior unsecured notes	11,157,732	11,420,790
Secured debt	2,304,178	2,377,930
Foreign currency forward contracts, interest rate swaps and cross currency swaps	89,929	118,054
Redeemable OP unitholder interests	148,332	116,240
Carrying Amount | Mortgage loans receivable
Financial assets:
Loans receivable	919,812	293,752
Carrying Amount | Other real estate loans receivable
Financial assets:
Loans receivable	177,487	149,620
Carrying Amount | Non-real estate loans receivable
Financial assets:
Loans receivable	198,364	240,269
Fair Value
Financial assets:
Equity securities	3,061	4,636
Cash and cash equivalents	513,602	1,545,046
Restricted cash	295,102	475,997
Foreign currency forward contracts, interest rate swaps and cross currency swaps	6,256	4,668
Equity warrants	32,419	0
Financial liabilities:
Senior unsecured notes	12,544,312	13,093,926
Secured debt	2,364,951	2,451,782
Foreign currency forward contracts, interest rate swaps and cross currency swaps	89,929	118,054
Redeemable OP unitholder interests	148,332	115,346
Fair Value | Mortgage loans receivable
Financial assets:
Loans receivable	935,528	297,207
Fair Value | Other real estate loans receivable
Financial assets:
Loans receivable	173,889	152,211
Fair Value | Non-real estate loans receivable
Financial assets:
Loans receivable	$ 202,877	$ 255,724

[1] Note: The consolidated balance sheet at December 31, 2020 has been derived from the audited financial statements at that date but does not include all of the information and footnotes required by U.S. generally accepted accounting principles for complete financial statements.