Financial Guarantee Insurance Contracts Financial Guarantee Insurance Contracts - Components of Loss and Loss Expense Reserves and Subrogation Recoverable (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013
Components of Loss and Loss Expense Reserves and Subrogation Recoverable [Line Items]
Ceded Loss And Loss Expenses Paid Not Yet Recovered	$ 4,789	$ (517)	$ 139
Loss Reserves Ceded To Reinsurers	74,519		100,355
Successor [Member]
Components of Loss and Loss Expense Reserves and Subrogation Recoverable [Line Items]
Loss Reserves Ceded To Reinsurers	74,519	111,303	100,355	122,357
Policyholder Benefits and Claims Incurred, Ceded	(20,601)	(10,559)
Liability for Unpaid Claims and Claims Adjustment Expense, Net	3,417,343	5,202,630	3,698,378	5,347,877
Loss and loss expense reserves	4,475,991		4,752,007
Subrogation recoverable	(984,129)		(953,274)
Claim liability reported on Balance Sheet, before reinsurance	3,491,862		3,798,733
Successor [Member] | Unpaid Claims-Claims [Member]
Components of Loss and Loss Expense Reserves and Subrogation Recoverable [Line Items]
Loss and loss expense reserves	2,158,007		2,172,041
Subrogation recoverable	774,960		772,948
Claim liability reported on Balance Sheet, before reinsurance	2,932,967		2,944,989
Successor [Member] | Unpaid Claims-Accrued Interest [Member]
Components of Loss and Loss Expense Reserves and Subrogation Recoverable [Line Items]
Loss and loss expense reserves	265,708		234,802
Subrogation recoverable	103,429		94,425
Claim liability reported on Balance Sheet, before reinsurance	369,137		329,227
Successor [Member] | Present Value of Expected Net Cash Flows- Claims and Loss Expenses [Member]
Components of Loss and Loss Expense Reserves and Subrogation Recoverable [Line Items]
Loss and loss expense reserves	3,579,957		3,792,133
Subrogation recoverable	175,415		197,751
Claim liability reported on Balance Sheet, before reinsurance	3,755,372		3,989,884
Successor [Member] | Present Value of Expected Net Cash Flows-Recoveries [Member]
Components of Loss and Loss Expense Reserves and Subrogation Recoverable [Line Items]
Loss and loss expense reserves	(1,268,916)		(1,205,621)
Subrogation recoverable	(2,037,933)		(2,018,398)
Claim liability reported on Balance Sheet, before reinsurance	(3,306,849)		(3,224,019)
Successor [Member] | Unearned Premium Reserve [Member]
Components of Loss and Loss Expense Reserves and Subrogation Recoverable [Line Items]
Loss and loss expense reserves	(258,765)		(241,348)
Subrogation recoverable	0		0
Claim liability reported on Balance Sheet, before reinsurance	$ (258,765)		$ (241,348)