Secured Debt, Net - Additional Information (Detail)	3 Months Ended		12 Months Ended
	Mar. 31, 2022 USD ($) credit_facility	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)
Debt Instrument [Line Items]
Interest expense	$ 100,714,000	$ 78,372,000
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	$ 1,651,729,000		$ 7,763,563,000
Collateral	$ 18,710,706,000		17,042,381,000
Number of new secured credit facilities | credit_facility	1
Maximum borrowing capacity	$ 1,000,000,000.0
Number of existing secured credit facilities with increased size | credit_facility	3
Additional credit capacity	$ 417,800,000
Remaining borrowing capacity	1,200,000,000
Borrowings	13,117,249,000		12,299,580,000
Secured credit facilities | Line of Credit | New Borrowings
Debt Instrument [Line Items]
New borrowings	2,100,000,000
Collateral	2,700,000,000
Acquisition facility | Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity	250,000,000
Borrowings	0		0
Interest expense	306,000		1,200,000
Amortization of deferred fees and expenses	$ 87,000		$ 354,000