Segment Reporting - Schedule of Assets by Segment (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	$ 4,314,635	$ 4,317,538
Business segments \| Single-Family
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	3,744,275	3,757,261
Business segments \| Multifamily
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	$ 570,360	$ 560,277

Amount of asset recognized for present right to economic benefit.

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+ Details