Loans and Investments - Allowance for Credit Losses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Allowance for credit losses:
Allowance at beginning of the year	$ 113,241	$ 148,329
Provision for credit losses (net of recoveries)	19,318	(24,315)	$ 59,966
Charge-offs		(10,773)
Allowance at end of the year	132,559	113,241	148,329
Amount of loan loss recovery	1,500	24,315	75
Outstanding unfunded commitments on loans	1,150,000	975,200
Accrued interest receivable related to loans	108,500	58,300
As Reported Pre-Adoption
Allowance for credit losses:
Allowance at beginning of the year			71,069
Impact of Adoption
Allowance for credit losses:
Allowance at beginning of the year			17,294
Land
Allowance for credit losses:
Allowance at beginning of the year	77,970	78,150
Provision for credit losses (net of recoveries)	98	(180)	10,204
Allowance at end of the year	78,068	77,970	78,150
Land | As Reported Pre-Adoption
Allowance for credit losses:
Allowance at beginning of the year			67,869
Land | Impact of Adoption
Allowance for credit losses:
Allowance at beginning of the year			77
Multifamily
Allowance for credit losses:
Allowance at beginning of the year	18,707	36,468
Provision for credit losses (net of recoveries)	19,254	(17,761)	20,146
Allowance at end of the year	37,961	18,707	36,468
Multifamily | Impact of Adoption
Allowance for credit losses:
Allowance at beginning of the year			16,322
Office
Allowance for credit losses:
Allowance at beginning of the year	8,073	1,846
Provision for credit losses (net of recoveries)	89	6,227	59
Allowance at end of the year	8,162	8,073	1,846
Office | As Reported Pre-Adoption
Allowance for credit losses:
Allowance at beginning of the year			1,500
Office | Impact of Adoption
Allowance for credit losses:
Allowance at beginning of the year			287
Retail
Allowance for credit losses:
Allowance at beginning of the year	5,819	13,861
Provision for credit losses (net of recoveries)		(42)	13,526
Charge-offs		(8,000)
Allowance at end of the year	5,819	5,819	13,861
Retail | Impact of Adoption
Allowance for credit losses:
Allowance at beginning of the year			335
Student Housing
Allowance for credit losses:
Allowance at beginning of the year	636	4,078
Provision for credit losses (net of recoveries)	(598)	(3,442)	4,010
Allowance at end of the year	38	636	4,078
Student Housing | Impact of Adoption
Allowance for credit losses:
Allowance at beginning of the year			68
Healthcare
Allowance for credit losses:
Allowance at beginning of the year	8	3,880
Provision for credit losses (net of recoveries)	8	(1,099)	3,816
Charge-offs		(2,773)
Allowance at end of the year	16	8	3,880
Healthcare | Impact of Adoption
Allowance for credit losses:
Allowance at beginning of the year			64
Hotel
Allowance for credit losses:
Allowance at beginning of the year	8	7,759
Provision for credit losses (net of recoveries)	6	(7,751)	7,730
Allowance at end of the year	14	8	7,759
Hotel | Impact of Adoption
Allowance for credit losses:
Allowance at beginning of the year			29
Other Property
Allowance for credit losses:
Allowance at beginning of the year	2,020	2,287
Provision for credit losses (net of recoveries)	461	(267)	475
Allowance at end of the year	$ 2,481	$ 2,020	2,287
Other Property | As Reported Pre-Adoption
Allowance for credit losses:
Allowance at beginning of the year			1,700
Other Property | Impact of Adoption
Allowance for credit losses:
Allowance at beginning of the year			$ 112