FANNIE MAE COMMITMENTS AND PLEDGED SECURITIES - Agency Multifamily Mortgage Based Securities Pledged Securities (Detail) - Agency Mortgage Backed Securities - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Investments in Agency debt securities
Fair Value	$ 139,411	$ 104,263
Amortized Cost	139,737	100,847
Total gains for securities with net gains in AOCI	1,242	3,636
Total losses for securities with net losses in AOCI	(1,568)	(220)
Fair value of securities with unrealized losses	104,433	4,757
Maturities - Fair Value
After one year through five years	13,901
After five years through ten years	100,704
After ten years	24,806
Total	139,411	104,263
Maturities - Amortized Cost
After one year through five years	13,903
After five years through ten years	100,835
After ten years	24,999
Total	$ 139,737	$ 100,847