Consolidated Statements of Total Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Change in fair value of credit derivatives:
Gain (Loss) on Sale of Derivatives	$ 43,443		$ 42,157
Successor [Member]
Revenues:
Net premiums earned	43,152	$ 41,402	90,765	$ 94,202
Net investment income:
Securities available-for-sale and short-term	80,943	64,368	154,093	122,350
Other investments	4,217	6,390	12,626	9,229
Total net investment income	85,160	70,758	166,719	131,579
Other-than-temporary impairment losses:
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities	(1,763)	(18,880)	(22,917)	(66,950)
Portion of other-than-temporary impairment recognized in other comprehensive income	0	11,439	17,212	50,175
Net other-than-temporary impairments	(1,763)	(7,441)	(5,705)	(16,775)
Available-for-sale Securities, Gross Realized Gain (Loss), Excluding Other than Temporary Impairments	4,180	14,897	(716)	15,999
Change in fair value of credit derivatives:
Gain (Loss) on Sale of Derivatives	1,134	233	1,333	485
Unrealized gains (losses)	5,490	3,722	6,343	16,336
Net change in fair value of credit derivatives	6,624	3,955	7,676	16,821
Net gains (losses) on interest rate derivatives	34,068	(36,331)	32,554	(119,755)
Net realized gains (losses) on extinguishment of debt	2,179	3,586	4,920	4,821
Other Operating Income (Expense), Net	467	6,919	381	14,918
Income (loss) on variable interest entities	(1,219)	8,987	2,482	(18,176)
Total revenues	172,848	106,732	299,076	123,634
Expenses:
Losses and loss expenses (benefit)	66,100	(52,496)	201,111	(157,777)
Insurance intangible amortization	33,471	39,013	70,996	89,903
Operating expenses	31,051	27,995	59,031	56,004
Interest expense	28,234	30,709	59,806	61,139
Total expenses	158,856	45,221	390,944	49,269
Pre-tax income (loss)	13,992	61,511	(91,868)	74,365
Provision for income taxes	6,882	3,156	26,463	6,595
Net income (loss)	7,110	58,355	(118,331)	67,770
Less: net gain (loss) attributable to noncontrolling interest	0	(292)	0	(292)
Net income (loss) attributable to common shareholders	7,110	58,647	(118,331)	68,062
Other comprehensive income (loss), after tax:
Net income (loss)	7,110	58,355	(118,331)	67,770
Unrealized gains (losses) on securities, net of deferred income taxes of $0	12,649	48,170	33,984	107,961
Gains (losses) on foreign currency translation, net of deferred income taxes of $0	29,292	(55,152)	41,885	(72,933)
Changes to postretirement benefit, net of tax of $0	(338)	(255)	1,949	532
Total other comprehensive income (loss), net of tax	41,603	(7,237)	77,818	35,560
Total comprehensive income (loss)	48,713	51,118	(40,513)	103,330
Less: comprehensive (gain) loss attributable to the noncontrolling interest:
Net gain (loss)	0	292	0	292
Total comprehensive income (loss) attributable to Ambac Financial Group, Inc.	$ 48,713	$ 51,410	$ (40,513)	$ 103,622
Earnings Per Share, Basic	$ 0.16	$ 1.30	$ (2.61)	$ 1.51
Earnings Per Share, Diluted	$ 0.16	$ 1.29	$ (2.61)	$ 1.50