Accumulated Other Comprehensive Loss (Tables)

9 Months Ended

Sep. 30, 2023

AOCI Attributable to Parent [Abstract]

Schedule of changes in accumulated other comprehensive loss

			Income
			Tax
	Pre-tax		Benefit		Net of
(dollars in thousands)	Amount		(Expense)		Tax
Accumulated other comprehensive loss at June 30, 2023	$	(835,647)	$	222,911	$	(612,736)
Three months ended September 30, 2023
Investment securities:
Unrealized net losses arising during the period		(61,874)		16,505		(45,369)
Reclassification of net losses to net income:
Amortization of unrealized holding losses on held-to-maturity securities		11,434		(3,050)		8,384
Net change in investment securities		(50,440)		13,455		(36,985)
Cash flow derivative hedges:
Unrealized net losses arising during the period		(373)		100		(273)
Reclassification of net losses included in net income		1,723		(460)		1,263
Net change in cash flow derivative hedges		1,350		(360)		990
Other comprehensive loss		(49,090)		13,095		(35,995)
Accumulated other comprehensive loss at September 30, 2023	$	(884,737)	$	236,006	$	(648,731)

			Income
			Tax
	Pre-tax		Benefit		Net of
(dollars in thousands)	Amount		(Expense)		Tax
Accumulated other comprehensive loss at December 31, 2022	$	(871,813)	$	232,559	$	(639,254)
Nine months ended September 30, 2023
Investment securities:
Unrealized net losses arising during the period		(50,861)		13,567		(37,294)
Reclassification of net losses to net income:
Amortization of unrealized holding losses on held-to-maturity securities		36,206		(9,658)		26,548
Net change in investment securities		(14,655)		3,909		(10,746)
Cash flow derivative hedges:
Unrealized net losses arising during the period		(2,868)		765		(2,103)
Reclassification of net losses included in net income		4,599		(1,227)		3,372
Net change in cash flow derivative hedges		1,731		(462)		1,269
Other comprehensive loss		(12,924)		3,447		(9,477)
Accumulated other comprehensive loss at September 30, 2023	$	(884,737)	$	236,006	$	(648,731)

			Income
			Tax
	Pre-tax		Benefit		Net of
(dollars in thousands)	Amount		(Expense)		Tax
Accumulated other comprehensive loss at June 30, 2022	$	(779,352)	$	207,895	$	(571,457)
Three months ended September 30, 2022
Investment securities:
Unrealized net losses arising during the period		(130,000)		34,677		(95,323)
Reclassification of net losses to net income:
Amortization of unrealized holding losses on held-to-maturity securities		15,217		(4,058)		11,159
Net change in investment securities		(114,783)		30,619		(84,164)
Cash flow derivative hedges:
Unrealized net losses arising during the period		(4,372)		1,165		(3,207)
Reclassification of net losses included in net income		98		(26)		72
Net change in cash flow derivative hedges		(4,274)		1,139		(3,135)
Other comprehensive loss		(119,057)		31,758		(87,299)
Accumulated other comprehensive loss at September 30, 2022	$	(898,409)	$	239,653	$	(658,756)

			Income
			Tax
	Pre-tax		Benefit		Net of
(dollars in thousands)	Amount		(Expense)		Tax
Accumulated other comprehensive loss at December 31, 2021	$	(165,967)	$	44,274	$	(121,693)
Nine months ended September 30, 2022
Investment securities:
Unrealized net losses arising during the period		(759,437)		202,580		(556,857)
Reclassification of net losses to net income:
Amortization of unrealized holding losses on held-to-maturity securities		35,146		(9,375)		25,771
Net change in investment securities		(724,291)		193,205		(531,086)
Cash flow derivative hedges:
Unrealized net losses arising during the period		(7,611)		2,030		(5,581)
Reclassification of net gains included in net income		(540)		144		(396)
Net change in cash flow derivative hedges		(8,151)		2,174		(5,977)
Other comprehensive loss		(732,442)		195,379		(537,063)
Accumulated other comprehensive loss at September 30, 2022	$	(898,409)	$	239,653	$	(658,756)

Summary of changes in accumulated other comprehensive loss, net of tax

	Pensions								Accumulated
	and		Available-for-Sale		Held-to-Maturity		Cash Flow		Other
	Other		Investment		Investment		Derivative		Comprehensive
(dollars in thousands)	Benefits		Securities		Securities		Hedges		Loss
Three Months Ended September 30, 2023
Balance at beginning of period	$	(5,431)	$	(284,100)	$	(318,782)	$	(4,423)	$	(612,736)
Other comprehensive (loss) income		—		(45,369)		8,384		990		(35,995)
Balance at end of period	$	(5,431)	$	(329,469)	$	(310,398)	$	(3,433)	$	(648,731)
Nine Months Ended September 30, 2023
Balance at beginning of period	$	(5,431)	$	(292,175)	$	(336,946)	$	(4,702)	$	(639,254)
Other comprehensive (loss) income		—		(37,294)		26,548		1,269		(9,477)
Balance at end of period	$	(5,431)	$	(329,469)	$	(310,398)	$	(3,433)	$	(648,731)
Three Months Ended September 30, 2022
Balance at beginning of period	$	(24,390)	$	(220,021)	$	(324,204)	$	(2,842)	$	(571,457)
Unrealized net losses related to the transfer of securities from available-for-sale to held-to-maturity		—		33,603		(33,603)		—		—
Other comprehensive (loss) income		—		(95,323)		11,159		(3,135)		(87,299)
Balance at end of period	$	(24,390)	$	(281,741)	$	(346,648)	$	(5,977)	$	(658,756)
Nine Months Ended September 30, 2022
Balance at beginning of period	$	(24,390)	$	(97,303)	$	—	$	—	$	(121,693)
Unrealized net losses related to the transfer of securities from available-for-sale to held-to-maturity		—		372,419		(372,419)		—		—
Other comprehensive (loss) income		—		(556,857)		25,771		(5,977)		(537,063)
Balance at end of period	$	(24,390)	$	(281,741)	$	(346,648)	$	(5,977)	$	(658,756)