Equity-based Compensation (Tables)

12 Months Ended

Dec. 31, 2024

Share-Based Payment Arrangement [Abstract]

Schedule of Share-based Payments Liability

The following table presents the changes in the share-based payments liability for the years ended December 31 (in millions):

	2024		2023		2022
Balance, beginning of period	$	23.0	$	19.4	$	28.1
Amortization and revaluation of granted awards	10.5		6.2		(4.6)
Repurchases (cash-settled)	(8.1)		(2.6)		(4.1)
Balance, end of period	$	25.4	$	23.0	$	19.4

Schedule of Activity of Share-based Compensation

Grants of restricted stock in Acadian Asset Management Inc.

The following table summarizes the activity related to restricted stock awards:

	2024			2023			2022
Acadian Asset Management Inc. RSAs	Number of shares	Weighted average grant date fair value per share		Number of shares	Weighted average grant date fair value per share		Number of shares	Weighted average grant date fair value per share
Outstanding at beginning of the year	—	$	—	—	$	—	2,500	$	10.09
Granted during the year	—	—		—	—		—	—
Forfeited during the year	—	—		—	—		(125)	10.09
Vested during the year	—	—		—	—		(2,375)	10.09
Outstanding at end of the year	—	$	—	—	$	—	—	$	—

The following table summarizes the activity related to restricted stock units:

	2024			2023			2022
Acadian Asset Management Inc. RSUs	Number of shares	Weighted average grant date fair value per share		Number of shares	Weighted average grant date fair value per share		Number of shares	Weighted average grant date fair value per share
Outstanding at beginning of the year	48,797	$	24.19	71,664	$	20.95	38,703	$	15.33
Granted during the year	44,639	21.68		49,494	24.04		59,999	22.62
Forfeited during the year	—	—		(15,823)	25.05		(3,003)	17.55
Vested during the year	(30,747)	23.54		(56,538)	19.72		(24,035)	16.51
Outstanding at end of the year	62,689	$	22.80	48,797	$	24.19	71,664	$	20.95

The following table summarizes the activity related to performance-based restricted stock units:

	2024			2023			2022
Acadian Asset Management Inc. Performance-based RSUs	Number of shares	Weighted average grant date fair value per share		Number of shares	Weighted average grant date fair value per share		Number of shares	Weighted average grant date fair value per share
Outstanding at beginning of the year	—	$	—	—	$	—	9,013	$	14.62
Vested during the year	—	—		—	—		(7,932)	14.62
Other movements	—	—		—	—		(1,081)	14.62
Outstanding at end of the year	—	$	—	—	$	—	—	$	—

The following tables summarizes the activity related to the Company’s stock option awards:

	2024
	Stock Options	Weighted average exercise price		Weighted average remaining contractual term (in years)	Aggregate intrinsic value
Outstanding at beginning of the year	1,659,000	$	10.64	0.8
Granted during the year	—	—
Forfeited during the year	—	—
Exercised during the year	(1,659,000)	10.64
Outstanding at end of the year	—	$	—	0.0	$	—
Exercisable at end of the year	—	$	—	0.0	$	—

	2023
	Stock Options	Weighted average exercise price		Weighted average remaining contractual term (in years)	Aggregate intrinsic value
Outstanding at beginning of the year	2,470,463	$	10.97	1.6
Granted during the year	—	—
Forfeited during the year	(75,000)	10.00
Exercised during the year	(736,463)	11.80
Outstanding at end of the year	1,659,000	$	10.64	0.8	$	14,128,440
Exercisable at end of the year	1,659,000	$	10.64	0.8	$	14,128,440

	2022
	Stock Options	Weighted average exercise price		Weighted average remaining contractual term (in years)	Aggregate intrinsic value
Outstanding at beginning of the year	2,969,963	$	11.09	2.5
Exercised during the year	(499,500)	11.70
Outstanding at end of the year	2,470,463	$	10.97	1.6	$	23,746,573
Exercisable at end of the year	1,441,463	$	11.03	1.5	$	13,767,753