Income Taxes (Tables)

12 Months Ended

Dec. 31, 2022

Income Tax Disclosure [Abstract]

Summary of Income Tax Assets and Liabilities

The income tax assets and liabilities included in Other assets and Other liabilities, respectively, in the Consolidated Balance Sheets were as follows:

($ in millions)	December 31,
	2022		2021
Income tax (asset) liability
Current	$	(18.8)	$	(9.5)
Deferred	6.2		190.5

Summary of Deferred Tax Assets and Liabilities

The "temporary differences" that gave rise to the deferred tax balances were as follows:

($ in millions)	December 31,
	2022		2021
Deferred tax assets
Other comprehensive income - net unrealized losses on securities	$	105.8	$	—
Unearned premium reserve reduction	10.1		11.7
Compensation accruals	8.4		9.6
Impaired securities	2.0		2.3
Other comprehensive income - net funded status of benefit plans	2.3		2.7
Discounting of unpaid claims and claim expense tax reserves	2.8		2.5
Net operating loss carryforward	3.6		—
Intangibles	0.1		0.1
Postretirement benefits other than pensions	0.2		0.3
Total gross deferred tax assets	135.3		29.2
Deferred tax liabilities
Other comprehensive income - net unrealized gains on securities	—		101.1
Deferred policy acquisition costs	73.0		37.3
Life insurance future policy benefit reserve	30.9		30.7
Life insurance future policy benefit reserve (transitional rule)	6.4		8.5
Discounting of unpaid claims and claim expense tax reserves (transitional rule)	0.5		0.6
Investment related adjustments	29.9		37.3
Other, net	0.8		4.2
Total gross deferred tax liabilities	141.5		219.7
Net deferred tax liability	$	6.2	$	190.5

Summary of Income Taxes Expenses

The components of the provision for income tax expense (benefit) were as follows:

($ in millions)	Years Ended December 31,
	2022		2021		2020
Current	$	(0.7)	$	27.7	$	16.9
Deferred	(8.6)		4.4		9.4
Total income tax expense (benefit)	$	(9.3)	$	32.1	$	26.3

Summary of Income Taxes Expenses Reconciliation

Income tax expense for the following periods differed from the expected tax computed by applying the federal corporate tax rate of 21% for 2022, 2021 and 2020 to income before income taxes as follows:

($ in millions)	Years Ended December 31,
	2022		2021		2020
Expected federal tax on income	$	(2.5)	$	36.7	$	33.5
Add (deduct) tax effects of:
Tax-exempt interest	(3.3)		(3.9)		(4.2)
Dividend received deduction	(3.2)		(2.2)		(1.5)
Goodwill impairment	—		—		0.2
CARES Act net operating loss carryback	—		—		(2.8)
Employee share-based compensation	(0.5)		(1.3)		(0.5)
Contingent consideration	(0.3)		—		—
Compensation deduction limitation	0.7		1.5		0.7
Research and development reserve	(0.4)		—		0.2
Prior year adjustments	0.1		0.1		(0.2)
Other, net	0.1		1.2		0.9
Income tax expense (benefit) provided on income	$	(9.3)	$	32.1	$	26.3

Summary of Unrecognized Tax Benefits, Excluding Interest and Penalties

A reconciliation of the beginning and ending amounts of unrecognized tax benefits, excluding interest and penalties, is as follows:

($ in millions)	Years Ended December 31,
	2022		2021		2020
Balance as of the beginning of the year	$	1.7	$	2.3	$	2.0
Increases related to prior year tax positions	—		—		0.2
Decreases related to prior year tax positions	—		(0.1)		—
Increases related to current year tax positions	—		—		0.1
Settlements	—		—		—
Lapse of statute	(1.3)		(0.5)		—
Balance as of the end of the year	$	0.4	$	1.7	$	2.3