Comprehensive Income - Components of Other Comprehensive Income (Loss) and Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) to Net Income (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance, before tax	$ (1,066,177)	$ (172,054)
Unrealized holding gains (losses), net, before tax	89,198	(184,955)
Foreign currency translation adjustment, before tax	1,807	(2,123)
Unrealized gain (losses) on cash flow hedges	51,038	(115,724)
Total other comprehensive income (loss) before reclassifications, before tax	142,043	(302,802)
Amortization of unrealized holding losses on held-to-maturity securities		1,119
Accretion of net gain on terminated cash flow hedges, before tax	(30)	(30)
Net yield adjustment from cash flow hedges currently in effect, before tax	59,039	(38,019)
Amortization of prior service credit, before tax	(475)	(950)
Amortization of actuarial losses, before tax	(1,550)	4,300
Total other comprehensive income (loss), before tax	199,027	(336,382)
Ending balance, before tax	(867,150)	(508,436)
Beginning balance, tax	276,147	44,476
Unrealized holding losses, net, tax	(24,058)	47,758
Foreign currency translation adjustment, tax	(613)	475
Unrealized losses on cash flow hedges, tax	(13,503)	29,885
Total other comprehensive income (loss) before reclassifications, tax	(38,174)	78,118
Amortization of unrealized holding losses on held-to-maturity securities, tax		(289)
Accretion of net gain on terminated cash flow hedges, tax	8	9
Net yield adjustment from cash flow hedges currently in effect, tax	(15,619)	9,818
Amortization of prior service credit, tax	(51)	305
Amortization of actuarial losses, tax	(166)	(1,386)
Total other comprehensive income (loss), tax	(54,002)	86,575
Ending balance, tax	222,145	131,051
Beginning balance, net of tax	(790,030)	(127,578)
Unrealized holding losses, net of tax	65,140	(137,197)
Foreign currency translation adjustments, net of tax	1,194	(1,648)
Unrealized losses on cash flow hedges, net of tax	37,535	(85,839)
Total other comprehensive income (loss) before reclassifications, net of tax	103,869	(224,684)
Amortization of unrealized holding losses on held-to-maturity securities		830
Accretion of net gain on terminated cash flow hedges, net of tax	(22)	(21)
Net yield adjustment from cash flow hedges currently in effect, net of tax	43,420	(28,201)
Amortization of prior service credit, net of tax	(526)	(645)
Amortization of actuarial losses, net of tax	(1,716)	2,914
Total other comprehensive income (loss)	145,025	(249,807)
Ending balance, net of tax	(645,005)	(377,385)
Defined Benefit Plans [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance, before tax	(272,856)	(360,276)
Amortization of prior service credit, before tax	(475)	(950)
Amortization of actuarial losses, before tax	(1,550)	4,300
Total other comprehensive income (loss), before tax	(2,025)	3,350
Ending balance, before tax	(274,881)	(356,926)
Total other comprehensive income (loss)	(2,242)
Other [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance, before tax	(349,129)	83,531
Foreign currency translation adjustment, before tax	1,807	(2,123)
Unrealized gain (losses) on cash flow hedges	51,038	(115,724)
Total other comprehensive income (loss) before reclassifications, before tax	52,845	(117,847)
Accretion of net gain on terminated cash flow hedges, before tax	(30)	(30)
Net yield adjustment from cash flow hedges currently in effect, before tax	59,039	(38,019)
Total other comprehensive income (loss), before tax	111,854	(155,896)
Ending balance, before tax	(237,275)	(72,365)
Investment Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance, before tax	(444,192)	104,691
Unrealized holding gains (losses), net, before tax	89,198	(184,955)
Total other comprehensive income (loss) before reclassifications, before tax	89,198	(184,955)
Amortization of unrealized holding losses on held-to-maturity securities		1,119
Total other comprehensive income (loss), before tax	89,198	(183,836)
Ending balance, before tax	(354,994)	$ (79,145)
Total other comprehensive income (loss)	$ 65,140