Notes Payable and Revolving Lines of Credit - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) extension_option	Dec. 31, 2019 USD ($)
Line of Credit
Debt Instrument [Line Items]
Number of extension options | extension_option	2
Extension term	6 months
Line of Credit | Base rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.00%
Line of Credit | Base rate | Investment grade election | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	0.00%
Line of Credit | Base rate | Investment grade election | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	1.25%
Line of Credit | Federal funds rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%
Line of Credit | Eurodollar
Debt Instrument [Line Items]
Basis spread on variable rate	1.00%
Line of Credit | Eurodollar | Investment grade election | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	0.75%
Line of Credit | Eurodollar | Investment grade election | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%
Notes Payable
Debt Instrument [Line Items]
Notes payable	$ 4,818,771	$ 4,343,502
Notes payable subject to recourse	$ 1,969,323