Debt - Debt Summary (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Weighted Average Interest Rate	2.20%	2.20%
Debt	$ 15,666,872	$ 11,905,877
Credit Facilities [Member]
Debt Instrument [Line Items]
Weighted Average Interest Rate	0.60%	0.40%
Debt	$ 115,108	$ 184,255
Senior Notes [Member]
Debt Instrument [Line Items]
Weighted Average Interest Rate	2.30%	2.40%
Debt	$ 13,205,392	$ 9,660,570
Term Loans and Unsecured Other [Member]
Debt Instrument [Line Items]
Weighted Average Interest Rate	1.00%	0.90%
Debt	$ 1,695,026	$ 1,441,882
Secured Mortgage [Member]
Debt Instrument [Line Items]
Weighted Average Interest Rate	3.60%	3.40%
Debt	$ 651,346	$ 619,170