Consolidated Statements of Cash Flows - Successor [Member] - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash flows from operating activities:
Net income attributable to common shareholders	$ (118,331)	$ 68,062
Net gain (loss)	0	292
Net income (loss)	(118,331)	67,770
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation and amortization	533	637
Amortization of bond premium and discount	(83,180)	(56,353)
Share-based compensation	2,385	2,777
Deferred income taxes	146	(493)
Current income taxes	12,283	(537)
Unearned premiums, net	(63,820)	(143,098)
Losses and loss expenses, net	206,693	812,937
Ceded premiums payable	(2,865)	(7,767)
Investment income due and accrued	1,755	182
Premium receivables	8,378	89,962
Accrued interest payable	6,576	24,581
Amortization of insurance intangible assets	70,996	89,903
Net mark-to-market (gains) losses	(6,343)	(16,336)
Net realized investment gains	716	(15,999)
Other-than-temporary impairment charges	5,705	16,775
(Gain) loss on extinguishment of debt	(4,920)	(4,821)
Variable interest entity activities	(2,482)	18,176
Increase (Decrease) in Derivative Assets and Liabilities	(211,149)	80,783
Other, net	15,921	(85,060)
Net cash provided by (used in) operating activities	(161,003)	874,019
Cash flows from investing activities:
Proceeds from sales of bonds	885,507	303,807
Proceeds from matured bonds	390,309	585,274
Purchases of bonds	(986,364)	(1,416,297)
Proceeds from sales of other invested assets	177,805	34,499
Purchases of other invested assets	(161,375)	(145,788)
Change in short-term investments	(73,092)	(111,869)
Loans, net	(5,965)	591
Change in cash collateral receivable	73,174	(90,966)
Other, net	(4,534)	7,996
Net cash provided by (used in) investing activities	295,465	(832,753)
Cash flows from financing activities:
Paydowns of a secured borrowing	(16,929)	(13,630)
Proceeds from warrant exercises	0	2
Payments for Repurchase of Warrants	0	1,610
Warrants Purchased During Period Dollars	0
Payments for investment agreement draws	(82,358)	(17,989)
Payments for extinguishment of long-term debt	(69,499)	(19,550)
Payments Related to Tax Withholding for Share-based Compensation	(1,268)	0
Net cash used in financing activities	(170,054)	(52,777)
Effect of Exchange Rate on Cash and Cash Equivalents	(1,195)	(1,189)
Net cash flow	(36,787)	(12,700)
Cash and cash equivalents at beginning of period	91,025	35,744
Cash and cash equivalents end of period	54,238	23,044
Supplemental disclosure of cash flow information:
Income taxes	16,012	7,662
Decrease in long-term debt as a result of an exchange for investment securities	55,426	0
Long-term Debt [Member]
Supplemental disclosure of cash flow information:
Interest Paid	$ 37,471	$ 2,352