Secured Debt, Net - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2021 USD ($) credit_facility	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Interest expense	$ 340,223,000	$ 347,471,000	$ 458,503,000
Covenants, minimum tangible net worth	$ 3,500,000,000
Covenants, percentage of recourse indebtedness	0.05
Minimum
Debt Instrument [Line Items]
Covenants, EBITDA to fixed charges, in percent	1.4
Covenants, percentage of tangible assets on cash proceeds from equity issuances	0.75
Covenants, minimum cash liquidity amount	$ 10,000,000.0
Maximum
Debt Instrument [Line Items]
Covenants, percentage of tangible assets on cash proceeds from equity issuances	0.85
Covenants, indebtedness to total assets, in percent	0.8333
Secured credit facilities | Line of Credit
Debt Instrument [Line Items]
New borrowings	$ 7,763,563,000	898,516,000
Collateral	$ 17,042,381,000	12,040,907,000
Number of new credit facilities | credit_facility	2
Number of existing credit facilities with increased size | credit_facility	4
Maximum borrowing capacity	$ 2,500,000,000
Additional credit capacity	1,200,000,000
Remaining borrowing capacity	607,400,000
Borrowings	12,299,580,000	7,896,863,000
Secured credit facilities | Line of Credit | New Borrowings
Debt Instrument [Line Items]
New borrowings	10,500,000,000
Collateral	13,200,000,000
Acquisition facility | Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity	250,000,000
Remaining borrowing capacity	147,500,000
Interest expense	1,200,000	1,600,000
Amortization of deferred fees and expenses	$ 354,000	$ 685,000