Conservatorship, Senior Preferred Stock Purchase Agreement and Related Matters - Narrative (Details) - USD ($) shares in Millions, $ in Millions	1 Months Ended	3 Months Ended
	Sep. 30, 2008	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2024	Dec. 31, 2023
Related Parties [Line Items]
Net worth		$ 86,500
Senior preferred stock liquidation preference		203,505	$ 199,200		$ 195,224
Increase in net worth		$ 4,500	$ 4,300
Series 2008-2 Senior Preferred Stock
Related Parties [Line Items]
Stock issued (in shares)	1
Forecast
Related Parties [Line Items]
Senior preferred stock liquidation preference				$ 208,000
Related Party | Treasury
Related Parties [Line Items]
Percentage of common shares attributable to warrants		79.90%
Aggregate funding received from US Treasury pursuant to the senior preferred stock purchase agreement		$ 119,800
Total available funding from US Treasury pursuant to the senior preferred stock agreement		113,900
Treasury
Related Parties [Line Items]
Aggregate liquidation preference of senior preferred stock		$ 203,500