FAIR VALUE MEASUREMENTS - Schedule of Carrying Amounts and the Fair Values of the Company's Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Financial Assets:
Cash and cash equivalents	$ 299,315	$ 279,270	$ 328,698	$ 225,949
Restricted cash	22,772	25,156	$ 21,422	$ 17,676
Pledged securities	224,954	206,904
Loans held for sale	1,436,350	780,749
Loans held for investment, net	77,769	32,866
Derivative assets	$ 27,216	$ 30,175
Derivative Asset, Statement of Financial Position	Other assets	Other assets
Financial Liabilities:
Derivative liabilities	$ 1,718	$ 915
Derivative Liability, Statement of Financial Position	Other liabilities	Other liabilities
Contingent consideration liabilities	$ 9,663	$ 30,537
Secured borrowings	83,402	59,441
Warehouse notes payable	1,420,272	781,706
Corporate notes payable	829,218	768,044
Carrying Amount
Financial Assets:
Cash and cash equivalents	299,315	279,270
Restricted cash	22,772	25,156
Pledged securities	224,954	206,904
Loans held for sale	1,436,350	780,749
Loans held for investment, net	77,769	32,866
Derivative assets	27,216	30,175
Total financial assets	2,088,376	1,355,120
Financial Liabilities:
Derivative liabilities	1,718	915
Contingent consideration liabilities	9,663	30,537
Secured borrowings	83,402	59,441
Warehouse notes payable	1,420,272	781,706
Corporate notes payable	829,218	768,044
Total financial liabilities	2,344,273	1,640,643
Fair Value
Financial Assets:
Cash and cash equivalents	299,315	279,270
Restricted cash	22,772	25,156
Pledged securities	224,954	206,904
Loans held for sale	1,436,350	780,749
Loans held for investment, net	77,769	32,866
Derivative assets	27,216	30,175
Total financial assets	2,088,376	1,355,120
Financial Liabilities:
Derivative liabilities	1,718	915
Contingent consideration liabilities	9,663	30,537
Secured borrowings	83,402	59,441
Warehouse notes payable	1,420,662	781,972
Corporate notes payable	847,552	778,481
Total financial liabilities	$ 2,362,997	$ 1,651,346