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FANNIE MAE COMMITMENTS AND PLEDGED SECURITIES - Pledged Securities at Fair Value (Detail) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2022
Pledged securities
Pledged securities	$ 203,945	$ 184,081
Pledged Securities - Fannie Mae DUS Program
Pledged securities
Fair value of pledged securities in a continuous unrealized loss position for more than 12 months	77,700
Amortized cost of pledged securities in a continuous unrealized loss position for more than 12 months	78,800
Net unrealized loss of pledged securities in a continuous unrealized loss position for more than 12 months	1,100
Total pledged cash and cash equivalents
Pledged securities
Pledged securities	47,054	41,283	$ 46,558	$ 14,658
Restricted Cash - Pledged
Pledged securities
Pledged securities	10,708	2,727	10,523	5,788
Money Market Funds
Pledged securities
Pledged securities	36,346	38,556	36,035	8,870
Agency MBS
Pledged securities
Pledged securities	156,891	142,798	130,951	142,624
Asset Pledged as Collateral with Right \| Pledged Securities - Fannie Mae DUS Program
Pledged securities
Pledged securities	$ 203,945	$ 184,081	$ 177,509	$ 157,282