Employment Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2018

Schedule of Expected Benefit Payments [Table Text Block]

The following table sets forth projected benefit payments from Ambac’s postretirement plan over the next ten years for current retirees:



2019	$	364
2020	364
2021	377
2022	404
2023	429
2024-2028	2,464
Total	$	4,402

Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable [Table Text Block]

The amount of stock-based compensation expense and corresponding after-tax expense are as follows:



Year Ended December 31,	2018		2017 ⁽¹⁾		2016
Stock options	$	—	$	—	$	—
Restricted stock units	6,234		1,640		3,463
Performance awards ^{(2) (3)}	5,620		2,653		1,790
Total stock-based compensation	$	11,854	$	4,293	$	5,253
Total stock-based compensation (after-tax)	$	11,854	$	4,293	$	5,194

(1)

As discussed in Note 2. Basis of Presentation and Significant Accounting Policies , we adopted ASU 2016-09 as of January 1, 2017. One of the provisions of this ASU requires entities to make an accounting policy election with respect to forfeitures of share-based payment awards. We elected to account for forfeitures as they occur and adopted this provision of ASU 2016-09 using a modified retrospective approach resulting in recording a cumulative-effect adjustment to equity of $137.


(2)	Represents expense related to performance stock units portion of performance awards. Certain performance awards are split evenly between performance stock units and cash. Cash based compensation expense related to performance awards granted to US employees was $1,453, $1,565 and $1,790 for the years ended December 31, 2018, 2017 and 2016, respectively.


(3)	A performance award issued to Ambac's former Chief Executive Officer in the form of performance stock units was expensed during 2018.

Share-based Compensation, Stock Options, Activity [Table Text Block]

A summary of stock option activity for 2018 is as follows:



	Shares		Weighted Average Exercise Price		Aggregate Intrinsic Value		Weighted Average Remaining Contractual Life (in years)
Outstanding at beginning of period	126,667		$	24.03
Granted	—		—
Exercised	—		—
Forfeited or expired	(110,000	)	24.55
Outstanding at end of period	16,667		$	20.63	$	—
Exercisable	16,667		$	20.63	$	—	1.97

Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block]

A summary of RSU activity for 2018 is as follows:



	Shares		Weighted Average Grant Date Fair Value
Outstanding at beginning of period	221,803		$	18.93
Granted	461,116		16.35
Delivered or returned to plan ⁽¹⁾	(36,454	)	17.53
Forfeited	(1,437	)	15.09
Outstanding at end of period	645,028		$	17.17


(1)	When restricted stock unit awards issued by Ambac become taxable compensation to employees, shares may be withheld to cover the employee’s withholding taxes. For the year ended December 31, 2018, Ambac purchased 22,929 of shares from employees that settled restricted stock units to meet the required tax withholdings.

Schedule of Nonvested Performance-based Units Activity [Table Text Block]

A summary of PSU activity for 2018 is as follows:



	Shares		Weighted Average Grant Date Fair Value
Outstanding at beginning of period	322,943		$	21.06
Granted ⁽¹⁾	302,002		15.09
Delivered ⁽²⁾	(121,690	)	24.63
Forfeited ⁽¹⁾	(15,573	)	18.20
Performance adjustment ⁽³⁾	29,317		24.66
Outstanding at end of period	516,999		$	17.02


(1)	Represents performance share units at 100% of units granted for LTIP Awards.

(2)

Reflects the number of performance shares attributable to the performance goals attained over the completed performance period and for which service conditions have been met. When performance stock unit awards issued by Ambac become taxable compensation to employees, shares may be withheld to cover the employee’s withholding taxes. For the year ended December 31, 2018, Ambac purchased 50,297 of shares from employees that settled performance based restricted stock units to meet the required tax withholdings.


(3)	Represents the increase (decrease) in shares issued for awards granted in 2015 based upon the attainment of performance metrics at the end of the performance period.