Basis of Presentation and Significant Accounting Policies FX gain (loss) (Details) - Successor [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Foreign Currency Transaction Gain (Loss), before Tax	$ 6,465	$ (6,241)
Loss and Loss Reserves [Member]
Foreign Currency Transaction Gain (Loss), before Tax	5,827	(10,081)
Gain (Loss) on Investments [Member]
Foreign Currency Transaction Gain (Loss), before Tax	1,916	2,783
Premiums Receivable [Member]
Foreign Currency Transaction Gain (Loss), before Tax	(560)	2,709
Unrealized Gains Or (Losses) On Credit Derivative Contracts [Member]
Foreign Currency Transaction Gain (Loss), before Tax	(706)	(1,024)
Cash Equivalents [Member]
Foreign Currency Transaction Gain (Loss), before Tax	$ (12)	$ (628)