Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Retained Earnings/Accumulated Deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Common Stock Held in Treasury, at Cost [Member]	Noncontrolling Interest [Member]
Beginning balance (Predecessor [Member]) at Dec. 31, 2012	$ (3,246,967)	$ (6,297,264)	$ 625,385	$ 0	$ 3,080	$ 2,172,027	$ (410,755)	$ 660,560
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Total comprehensive income \| Predecessor [Member]	3,522,382	3,349,049	174,875	0	0	0	0	(1,542)
Stock-based compensation \| Predecessor [Member]	(60)	(60)	0	0	0	0	0	0
Cost of shares acquired \| Predecessor [Member]	60	0	0	0	0	0	60	0
Payments for Repurchase of Warrants \| Predecessor [Member]	0
Elimination of Predecessor Ambac Shareholder equity accounts and noncontrolling interest adjustment \| Predecessor [Member]	0	2,948,275	(800,260)	0	(3,080)	(2,172,027)	410,695	(383,603)
Ending balance (Successor [Member]) at Apr. 30, 2013	460,415
Ending balance (Predecessor [Member]) at Apr. 30, 2013	275,415	0	0	0	0	0	0	275,415
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total comprehensive income \| Successor [Member]	516,904
Stock-based compensation \| Successor [Member]	1,106
Payments for Repurchase of Warrants \| Successor [Member]	0
Ending balance (Successor [Member]) at Dec. 31, 2013	978,422	505,219	11,661	0	450	185,672	(19)	275,439
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of new equity in connection with emergence from Chapter 11 \| Successor [Member]	185,000	0	0	0	450	184,550	0	0
Beginning balance (Successor [Member]) at May. 01, 2013	460,415	0	0	0	450	184,550	0	275,415
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total comprehensive income \| Successor [Member]	516,904	505,219	11,661	0	0	0	0	24
Stock-based compensation \| Successor [Member]	1,106	0	0	0	0	1,106	0	0
Warrants exercised \| Successor [Member]	16	0	0	0	0	16	0	0
Cost of shares acquired \| Successor [Member]	(19)	0	0	0	0	0	(19)	0
Ending balance (Successor [Member]) at Dec. 31, 2013	978,422	505,219	11,661	0	450	185,672	(19)	275,439
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total comprehensive income \| Successor [Member]	691,884	484,071	208,622	0	0	0	0	(809)
Stock-based compensation \| Successor [Member]	3,450	0	0	0	0	3,450	0	0
Cost of shares acquired \| Successor [Member]	(37)	0	0	0	0	0	(37)	0
Payments for Repurchase of Warrants \| Successor [Member]	0
Warrants exercised \| Successor [Member]	16	0	0	0	0	16	0	0
Ending balance (Successor [Member]) at Dec. 31, 2014	1,673,735	989,290	220,283	0	450	189,138	(56)	274,630
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total comprehensive income \| Successor [Member]	287,252	493,403	(205,068)	0	0	0	0	(1,083)
Stock-based compensation \| Successor [Member]	3,105	0	0	0	0	3,105	0	0
Cost of shares acquired \| Successor [Member]	(374)	(312)	0	0	0	0	(62)	0
Payments for Repurchase of Warrants \| Successor [Member]	(5,375)	3,942	0	0	0	1,433	0	0
Warrants exercised \| Successor [Member]	3	0	0	0	0	3	0	0
Ending balance (Successor [Member]) at Dec. 31, 2015	$ 1,958,346	$ 1,478,439	$ 15,215	$ 0	$ 450	$ 190,813	$ (118)	$ 273,547

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The aggregate amount paid by the entity to reacquire the right to purchase equity shares at a predetermined price, usually issued together with corporate debt.

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Total stockholders' equity at the balance sheet date after fresh-start adjustments.

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Value of stock (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of stock value of such awards forfeited. Stock issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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Redemption of temporary equity as the result of a triggering event associated with the temporary equity.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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