Net Income Per Share (Tables)

12 Months Ended

Dec. 31, 2014

Earnings Per Share [Abstract]

Reconciliation of Common Shares Used for Basic and Diluted Earnings Per Share

The following table provides a reconciliation of the common shares used for basic net income per share to the diluted shares used for diluted net income per share:

	Successor Ambac		Predecessor Ambac
		Period from May 1	Period from January 1
	Year Ended	through	through	Year Ended
	December 31, 2014	December 31, 2013	April 30, 2013	December 31, 2012
Weighted average number of common shares used for basic earnings per share	45,093,304	45,003,925	302,469,544	302,468,867
Effect of potential dilutive shares:
Warrants	1,786,804	1,297,620	—	—
Stock options	9,807	—	—	—
Restricted stock units	37,812	1,189	109,701	—
Performance stock units	5,526	—	—	—
Weighted average number of common shares and potential dilutive shares used for diluted earnings per share	46,933,253	46,302,734	302,579,245	302,468,867
Anti-dilutive shares excluded from the above reconciliation:
Warrants	—	—	—	—
Stock options	—	855	475,550	805,999
Restricted stock units	—	—	—	71,295
Performance stock units	—	—	—	—