Employment Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2021

Postemployment Benefits [Abstract]

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:

2022	$	—
2023	—
2024	—
2025	1
2026	1
2025-2029	3
Total	$	5

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,	2021		2020		2019
Restricted stock units	5		3		4
Performance awards	10		8		8
Total stock-based compensation	$	14	$	11	$	12
Total stock-based compensation (after-tax)	$	14	$	11	$	12

Share-based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block]

A summary of RSU activity for 2021 is as follows:

	Shares	Weighted Average Grant Date Fair Value
Outstanding at beginning of period	773,657	$	18.04
Granted	345,829	$	17.39
Delivered or returned to plan (1)	(280,672)	$	17.89
Forfeited	(1,744)	$	18.34
Outstanding at end of period	837,070	$	17.82

(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, 2021, Ambac purchased 88,723 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 2021 is as follows:

	Shares	Weighted Average Grant Date Fair Value
Outstanding at beginning of period	844,514	$	18.09
Granted (1)	396,202	18.12
Delivered (2)	(804,217)	16.23
Forfeited	(4,355)	19.10
Performance adjustment (3)	289,912	15.09
Outstanding at end of period	722,056	$	18.97

(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, 2021, Ambac purchased 276,777 of shares from employees that settled performance based restricted stock units to meet the required tax withholdings.

(3)    Represents the number of additional shares issued for awards granted in 2018 as a result of actual performance during the performance period.