Loans Receivable, Net - Additional Information (Detail) $ in Thousands	3 Months Ended				6 Months Ended						12 Months Ended
	Jun. 30, 2025 USD ($) loan	Mar. 31, 2025 USD ($)	Jun. 30, 2024 USD ($)	Mar. 31, 2024 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2025 USD ($) loan	Jun. 30, 2025 USD ($) security_loan	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2024 USD ($) loan	Dec. 31, 2024 USD ($) security_loan	Dec. 31, 2023 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted-average risk rating	3.1				3.1	3.1	3.1	3.1	3.1		3.0	3.0	3.0
Net increase (decrease) in CECL reserve	$ (690)
Amount charged off	45,057	$ 41,824	$ 12,537	$ 61,013		$ 86,881					$ 384,603
CECL reserve	740,851	741,541	893,938	751,370	$ 740,851	740,851	$ 740,851	$ 740,851	$ 740,851	$ 893,938	733,936	$ 733,936	$ 733,936	$ 576,936
Interest and related income	359,537		466,152			691,594				952,275
Number of loans							144	144				130	130
Principal balance	19,706,105				19,706,105	19,706,105	$ 19,706,105	$ 19,706,105	19,706,105		19,047,518	$ 19,047,518	$ 19,047,518
Net book value	18,965,254				18,965,254	18,965,254	$ 18,965,254	18,965,254	18,965,254		18,313,582	18,313,582	18,313,582
Number of loan modifications | loan							10
Real estate owned, net	615,217				615,217	615,217	$ 615,217	615,217	615,217		588,185	588,185	588,185
Joint Venture
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan exposure	43,300				43,300	43,300	43,300	43,300	43,300		43,300	43,300	43,300
Real estate owned, net	32,200				32,200	32,200	$ 32,200	32,200	32,200		32,400	$ 32,400	32,400
5
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans | loan							14					13
Principal balance	1,591,620				1,591,620	1,591,620	$ 1,591,620	1,591,620	1,591,620		1,827,561	$ 1,827,561	1,827,561
4
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans | loan							18					20
Principal balance	2,788,227				2,788,227	2,788,227	$ 2,788,227	2,788,227	2,788,227		2,707,104	$ 2,707,104	2,707,104
3
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans | loan							87					65
Principal balance	11,908,048				11,908,048	11,908,048	$ 11,908,048	11,908,048	11,908,048		9,246,692	$ 9,246,692	9,246,692
2
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans | loan							17					21
Principal balance	2,942,069				$ 2,942,069	2,942,069	$ 2,942,069	2,942,069	$ 2,942,069		3,346,881	$ 3,346,881	3,346,881
Payment Deferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loan modifications | loan							2
Aggregate amortized cost basis of loans						379,100
Percentage to aggregate loans receivable portfolio									1.90%
Extended Maturity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loan modifications | loan							3
Aggregate amortized cost basis of loans						508,500
Percentage to aggregate loans receivable portfolio									2.60%
Extended Maturity | 5
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loan modifications | loan							5
Extended Maturity, Loan One
Accounts, Notes, Loans and Financing Receivable [Line Items]
Extension term					5 years
Proceeds from repayment of loan						6,000
Extended Maturity, Loan Two
Accounts, Notes, Loans and Financing Receivable [Line Items]
Extension term					3 years 9 months 18 days
Proceeds from repayment of loan						1,700
Extended Maturity, Loan Three
Accounts, Notes, Loans and Financing Receivable [Line Items]
Extension term					4 years 9 months 18 days
Increase (decrease) in rate									(0.10%)
Extended Maturity, Loan Four
Accounts, Notes, Loans and Financing Receivable [Line Items]
Extension term					1 year
Increase (decrease) in rate									(2.43%)
Proceeds from repayment of loan						25,000
Extended Maturity, Loan Five
Accounts, Notes, Loans and Financing Receivable [Line Items]
Extension term					4 years 3 months 18 days
Increase (decrease) in rate									(3.56%)
Extended Maturity, Senior Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loan modifications | loan							5
Extended Maturity, Senior Loans | 4
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loan modifications | loan							3
Extended Maturity, Senior Loans | 3
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loan modifications | loan							1
Extended Maturity, Senior Loans | 2
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loan modifications | loan							1
Office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans | loan							44					41
Principal balance	5,855,637				$ 5,855,637	5,855,637	$ 5,855,637	5,855,637	$ 5,855,637		7,386,333	$ 7,386,333	7,386,333
Number of loan modifications | loan							4
Hospitality
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans | loan							17					16
Principal balance	2,842,904				2,842,904	2,842,904	$ 2,842,904	2,842,904	2,842,904		2,768,374	$ 2,768,374	2,768,374
Mixed Use Asset
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loan modifications | loan							1
One Loan Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans | loan							1
Net book value	195,000				195,000	195,000	$ 195,000	195,000	195,000
One Loan Past Due | Junior Loan Participation
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net book value	50,000				50,000	50,000	$ 50,000	50,000	50,000
13 Loans | Impaired loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans | loan							14
Cash proceeds	10,800
Impaired loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount charged off	45,057	41,824	12,537	61,013
CECL reserve	$ 558,767	$ 555,379	$ 759,380	$ 602,599	558,767	558,767	$ 558,767	558,767	558,767	$ 759,380	580,651	580,651	580,651	$ 417,670
Number of new loans impaired | loan	2
Interest and related income	$ 5,300
Number of loans | loan	1
Principal balance	$ 1,591,620				1,591,620	1,591,620	1,591,620	1,591,620	1,591,620		1,827,561	1,827,561	1,827,561
Impaired loans | 5
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal balance	1,591,620				1,591,620	1,591,620	1,591,620	1,591,620	1,591,620		1,827,561	1,827,561	1,827,561
Impaired loans | 4
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal balance	0				0	0	0	0	0		0	0	0
Impaired loans | 3
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal balance	0				0	0	0	0	0		0	0	0
Impaired loans | 2
Accounts, Notes, Loans and Financing Receivable [Line Items]
Principal balance	0				0	0	$ 0	0	0		$ 0	$ 0	$ 0
Unfunded Loan Commitment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans | loan							58
Unfunded Loan Commitment | Payment Deferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unfunded loan commitments	4,700				4,700	4,700	$ 4,700	4,700	4,700
Unfunded Loan Commitment | Extended Maturity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unfunded loan commitments	32,700				$ 32,700	$ 32,700	$ 32,700	$ 32,700	$ 32,700
Asset-specific CECL Reserves
Accounts, Notes, Loans and Financing Receivable [Line Items]
(Decrease) increase in net CECL reserve	48,400
General CECL Reserves
Accounts, Notes, Loans and Financing Receivable [Line Items]
(Decrease) increase in net CECL reserve	$ (4,100)