Fair Value Measurements - Financial Instruments Carried at Fair Value on Recurring Basis (Details) - USD ($)		3 Months Ended
	Mar. 16, 2022	Mar. 31, 2024	Dec. 31, 2023
Assets:
Loans, held for sale, at fair value		$ 584,072,000	$ 81,599,000
Loans, net, fair value		0	9,348,000
Investments held to maturity		3,446,000	3,446,000
Derivative instruments		15,448,000	2,404,000
Investment in unconsolidated joint venture		7,169,000	7,360,000
Liabilities:
Derivative instruments, at fair value		593,000	212,000
Contingent consideration			7,628,000
Mosaic
Fair value
Fair value of CERs issued	$ 25,000,000.0	$ 0
Value per CER unit	$ 0.83
Minimum
Fair value
Return of capital assumption used in PWERM		65.00%
Maximum
Fair value
Return of capital assumption used in PWERM		100.00%
Recurring
Assets:
Cash held in money market funds		$ 63,040,000	100,238,000
Loans, held for sale, at fair value		86,099,000	81,599,000
Loans, net, fair value			9,348,000
Paycheck Protection Program loans		491,000	165,000
Mortgage backed securities, at fair value		29,546,000	27,436,000
Derivative instruments		15,448,000	2,404,000
Investment in unconsolidated joint venture		7,169,000	7,360,000
Preferred equity investments		106,548,000	108,423,000
Total assets		308,341,000	336,973,000
Liabilities:
Derivative instruments, at fair value		593,000	212,000
Contingent consideration			7,628,000
Total liabilities		593,000	7,840,000
Recurring | Level 1
Assets:
Cash held in money market funds		63,040,000	100,238,000
Total assets		63,040,000	100,238,000
Recurring | Level 2 inputs
Assets:
Loans, held for sale, at fair value		86,099,000	81,599,000
Paycheck Protection Program loans		491,000	165,000
Mortgage backed securities, at fair value		29,546,000	27,436,000
Derivative instruments		15,448,000	2,404,000
Total assets		131,584,000	111,604,000
Liabilities:
Derivative instruments, at fair value		593,000	212,000
Total liabilities		593,000	212,000
Recurring | Level 3 inputs
Assets:
Loans, net, fair value			9,348,000
Investment in unconsolidated joint venture		7,169,000	7,360,000
Preferred equity investments		106,548,000	108,423,000
Total assets		$ 113,717,000	125,131,000
Liabilities:
Contingent consideration			7,628,000
Total liabilities			$ 7,628,000