Accumulated Other Comprehensive Income (Tables)

6 Months Ended

Jun. 30, 2023

Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]

Components of Accumulated Other Comprehensive Income, Net of Tax

The following tables summarize those reclassification adjustments (net of taxes) for the periods indicated: 

	Three Months Ended June 30, 2023
	Foreign currency translation adjustment		Net unrealized losses on investments		Net unrealized gains on derivative transactions		Unamortized net losses on Pension Plans		Accumulated other comprehensive loss
Balance at March 31, 2023	$	(384.0)	$	(434.0)	$	9.9	$	(91.4)	$	(899.5)
Change in accumulated other comprehensive income (loss) before reclassifications	23.7		(54.8)		2.3		0.4		(28.4)
Amounts reclassified from accumulated other comprehensive income (loss)	—		7.9		(0.2)		(2.5)		5.2
Net current-period other comprehensive income (loss)	23.7		(46.9)		2.1		(2.1)		(23.2)
Balance at June 30, 2023	$	(360.3)	$	(480.9)	$	12.0	$	(93.5)	$	(922.7)
	Three Months Ended June 30, 2022
	Foreign currency translation adjustment		Net unrealized gains on investments		Net unrealized gains on derivative transactions		Unamortized net losses on Pension Plans		Accumulated other comprehensive income
Balance at March 31, 2022	$	(325.6)	$	(78.2)	$	11.8	$	(93.3)	$	(485.3)
Change in accumulated other comprehensive income (loss) before reclassifications	(41.9)		(305.0)		—		(0.6)		(347.5)
Amounts reclassified from accumulated other comprehensive income (loss)	—		13.1		(0.7)		(1.8)		10.6
Net current-period other comprehensive income (loss)	(41.9)		(291.9)		(0.7)		(2.4)		(336.9)
Balance at June 30, 2022	$	(367.5)	$	(370.1)	$	11.1	$	(95.7)	$	(822.2)
	Six Months Ended June 30, 2023
	Foreign currency translation adjustment		Net unrealized gains (losses) on investments		Net unrealized gains on derivative transactions		Unamortized net losses on Pension Plans		Accumulated other comprehensive loss
Balance at December 31, 2022	$	(394.0)	$	(513.2)	$	9.8	$	(88.8)	$	(986.2)
Change in accumulated other comprehensive income (loss) before reclassifications	33.7		21.2		3.4		0.3		58.6
Amounts reclassified from accumulated other comprehensive income (loss) (1)	—		11.1		(1.2)		(5.0)		4.9
Net current-period other comprehensive income (loss)	33.7		32.3		2.2		(4.7)		63.5
Balance at June 30, 2023	$	(360.3)	$	(480.9)	$	12.0	$	(93.5)	$	(922.7)
	Six Months Ended June 30, 2022
	Foreign currency translation adjustment		Net unrealized gains on investments		Net unrealized gains on derivative transactions		Unamortized net losses on Pension Plans		Accumulated other comprehensive income
Balance at December 31, 2021	$	(326.9)	$	256.6	$	12.4	$	(92.1)	$	(150.0)
Change in accumulated other comprehensive income (loss) before reclassifications	(40.6)		(652.8)		—		—		(693.4)
Amounts reclassified from accumulated other comprehensive income (loss)	—		26.1		(1.3)		(3.6)		21.2
Net current-period other comprehensive income (loss)	(40.6)		(626.7)		(1.3)		(3.6)		(672.2)
Balance at June 30, 2022	$	(367.5)	$	(370.1)	$	11.1	$	(95.7)	$	(822.2)

Reclassification out of Accumulated Other Comprehensive Income

The following tables summarize the reclassifications out of AOCI for the periods indicated:

Details about accumulated other comprehensive income components	Amount reclassified from accumulated other comprehensive income				Affected line item in the statement where net income is presented
	Three Months Ended June 30,
	2023		2022
Net unrealized losses (gains) on investments	$	10.0	$	16.6	Net realized losses (gains) on investments
	(2.1)		(3.5)		Provision for income taxes
	$	7.9	$	13.1	Net of tax
Net unrealized gains on derivative transactions	$	(0.7)	$	(0.9)	Interest expense
	0.4		—		Underwriting, selling, general and administrative expenses
	0.1		0.2		Provision for income taxes
	$	(0.2)	$	(0.7)	Net of tax
Amortization of pension and postretirement unrecognized net periodic benefit cost:
Amortization of net loss	$	0.3	$	1.1	(1)
Amortization of prior service credit	(3.4)		(3.4)		(1)
	(3.1)		(2.3)
	0.6		0.5		Provision for income taxes
	$	(2.5)	$	(1.8)	Net of tax
Total reclassifications for the period	$	5.2	$	10.6	Net of tax
Details about accumulated other comprehensive income components	Amount reclassified from accumulated other comprehensive income				Affected line item in the statement where net income is presented
	Six Months Ended June 30,
	2023		2022
Net unrealized losses (gains) on investments	$	14.0	$	33.0	Net realized losses (gains) on investments
	(2.9)		(6.9)		Provision for income taxes
	$	11.1	$	26.1	Net of tax
Net unrealized gains on derivative transactions	$	(2.0)	$	(1.6)	Interest expense
	0.4		—		Underwriting, selling, general and administrative expenses
	0.4		0.3		Provision for income taxes
	$	(1.2)	$	(1.3)	Net of tax
Amortization of pension and postretirement unrecognized net periodic benefit cost:
Amortization of net loss	$	0.6	$	2.2	(1)
Amortization of prior service credit	(6.8)		(6.8)		(1)
	(6.2)		(4.6)
	1.2		1.0		Provision for income taxes
	$	(5.0)	$	(3.6)	Net of tax
Total reclassifications for the period	$	4.9	$	21.2	Net of tax

(1)These AOCI components are included in the computation of net periodic pension cost. For additional information, see Note 13.