Employment Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2017

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:



2018		2019		2020		2021		2022		2023-2027		Total
$	282	$	311	$	327	$	353	$	387	$	2,452	$	4,112

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,	2017 ⁽¹⁾		2016		2015
Stock options	$	—	$	—	$	956
Restricted stock units	1,640		3,463		1,257
Performance awards ^{(2) (3)}	2,653		1,790		892
Total stock-based compensation	$	4,293	$	5,253	$	3,105
Total stock-based compensation (after-tax)	$	4,293	$	5,194	$	3,105

(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 $1,565, $1,790 and $892 for the years ended December 31, 2017, 2016 and 2015, respectively.

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

The following assumptions were used in estimating the fair value of options awarded in 2015:



Year Ended December 31,	2015
Risk-free interest rate	1.283		%
Expected volatility	42.8		%
Dividend yield	0.0		%
Expected life	4.13 years
Weighted-average grant-date fair value per share	$	8.69

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

A summary of option activity for 2017 is as follows:



	Shares		Weighted Average Exercise Price		Aggregate Intrinsic Value		Weighted Average Remaining Contractual Life ( in years)
Year Ended December 31, 2017
Outstanding at beginning of period	143,334		$	23.64
Granted	—		—
Exercised	—		—
Forfeited or expired	(16,667	)	20.63
Outstanding at end of period	126,667		$	24.03	$	—	1.23
Exercisable	126,667		$	24.03	$	—	1.23

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

A summary of RSU activity for 2017 is as follows:



	Shares		Weighted Average Grant Date Fair Value
Outstanding at beginning of period	264,230		$	16.47
Granted	70,432		20.22
Delivered or returned to plan ⁽¹⁾	(112,859	)	13.96
Forfeited	—		—
Outstanding at end of period	221,803		$	18.93


(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, 2017, Ambac purchased 56,410 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 2017 is as follows:



	Shares		Weighted Average Grant Date Fair Value
Outstanding at beginning of period	227,073		$	21.29
Granted ⁽¹⁾	153,317		22.35
Delivered ⁽²⁾	(38,464	)	29.78
Forfeited ⁽¹⁾	(26,378	)	20.26
Performance adjustment ⁽³⁾	7,395		29.78
Outstanding at end of period	322,943		$	21.06


(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.


(3)	Represents the increase (decrease) in shares issued for awards granted in 2014 based upon the attainment of performance metrics at the end of the performance period.