Income Taxes Income Taxes - NOL Usage Table (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($)
Net Income Loss Reconciliation [Line Items]
NOL allocated amount	$ 1,663,087
Loss Carryforward Indefinite Life	158,663
Ambac Assurance [Member]
Net Income Loss Reconciliation [Line Items]
NOL allocated amount	1,952,621
AFG [Member]
Net Income Loss Reconciliation [Line Items]
NOL allocated amount	$ 1,663,087
Minimum [Member] | Ambac Assurance [Member]
Net Income Loss Reconciliation [Line Items]
Operating Loss Carryforwards, Expiration Date	Dec. 31, 2030
Maximum [Member] | Ambac Assurance [Member]
Net Income Loss Reconciliation [Line Items]
Operating Loss Carryforwards, Expiration Date	Dec. 31, 2042