Segment Reporting - Segment Assets (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Segment Reporting [Line Items]
Total Assets	$ 3,532,205	$ 3,497,598
Reconciling items
Segment Reporting [Line Items]
Total Assets	(163,532)	(154,527)
Single Family Guarantee Segment \| Operating segments
Segment Reporting [Line Items]
Total Assets	3,186,153	3,156,290
Multifamily \| Operating segments
Segment Reporting [Line Items]
Total Assets	509,584	495,835
Operating segments \| Operating segments
Segment Reporting [Line Items]
Total Assets	$ 3,695,737	$ 3,652,125

Amount of asset recognized for present right to economic benefit.

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+ Details

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details