Consolidated Statements of Total Comprehensive Income - Successor [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Revenues:
Net premiums earned	$ 52,800	$ 65,718
Net investment income:
Securities available-for-sale and short-term	57,982	63,332
Other investments	2,839	9,651
Total net investment income	60,821	72,983
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities	48,070	10,361
Other-than-temporary impairment losses:
Portion of other-than-temporary impairment recognized in other comprehensive income	38,736	7,242
Net other-than-temporary impairments	(9,334)	(3,119)
Available-for-sale Securities, Gross Realized Gain (Loss), Excluding Other than Temporary Impairments	1,102	54,101
Gain (Loss) on Sale of Derivatives	252	419
Change in fair value of credit derivatives:
Unrealized gains (losses)	12,614	(2,918)
Net change in fair value of credit derivatives	12,866	(2,499)
Derivative products	(83,424)	(37,774)
Net realized gains (losses) on extinguishment of debt	1,235	(93)
Other Operating Income (Expense), Net	7,999	(788)
Income (loss) on variable interest entities	(27,163)	6,962
Total revenues	16,902	155,491
Expenses:
Losses and loss expense (benefit)	(105,281)	(150,952)
Insurance intangible amortization	50,890	37,432
Operating expenses	28,009	24,523
Interest expense	30,430	27,908
Total expenses (benefit)	4,048	(61,089)
Pre-tax income	12,854	216,580
Provision for income taxes	3,439	1,709
Net income	9,415	214,871
Less: net (gain) loss attributable to noncontrolling interest	0	160
Net income attributable to common stockholders	9,415	214,711
Other comprehensive income, after tax:
Net income	9,415	214,871
Unrealized gains (losses) on securities, net of deferred income taxes of $0	59,791	(17,448)
Gains (losses) on foreign currency translation, net of deferred income taxes of $0	(17,781)	(33,805)
Changes to postretirement benefit, net of tax of $0	787	(27)
Total other comprehensive income (loss), net of tax	42,797	(51,280)
Total comprehensive income	52,212	163,591
Less: comprehensive (loss) gain attributable to the noncontrolling interest:
Net (gain) loss	0	160
Currency translation adjustments	0	(326)
Total comprehensive income attributable to Ambac Financial Group, Inc.	$ 52,212	$ 163,757
Net income per share attributable to Ambac Financial Group, Inc. common stockholders	$ 0.21	$ 4.75
Basic	$ 0.21	$ 4.57