FANNIE MAE COMMITMENTS AND PLEDGED SECURITIES - Commitments (Detail) - Fannie Mae $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($)
LITIGATION, COMMITMENTS, AND CONTINGENCIES
Period of funding for collateral requirement	48 months
Money Market Funds
LITIGATION, COMMITMENTS, AND CONTINGENCIES
Restricted liquidity collateral reduction percentage	5.00%
Agency Mortgage Backed Securities
LITIGATION, COMMITMENTS, AND CONTINGENCIES
Restricted liquidity collateral reduction percentage	4.00%
New Tier 2 loans
LITIGATION, COMMITMENTS, AND CONTINGENCIES
Collateral requirements percentage	0.75%
DUS Risk-Sharing Obligations
LITIGATION, COMMITMENTS, AND CONTINGENCIES
Period of funding for collateral requirement	48 months
Amount of additional capital required to be funded over the next 48 months	$ 65.3
Net worth requirement	258.2
Net worth	722.4
Minimum liquid assets to be maintained to meet operational liquidity requirements	51.1
Operational liquidity	$ 251.7

Amount of net capital of broker-dealer.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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