CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands		Total	Cumulative effect adoption adjustment	Common Stock	Preferred Stock	Capital surplus	Retained earnings	Retained earnings Cumulative effect adoption adjustment	Treasury stock	Accumulated other comprehensive income (loss)
Beginning balance at Dec. 31, 2021		$ 5,969,397		$ 1,046	$ 22,143	$ 4,650,182	$ 2,973,745		$ (1,352,650)	$ (325,069)
Increase Decrease In Stockholders Equity
Net income		423,107					423,107
Issuance of stock		2,735				2,735
Dividends declared:
Common stock	[1]	(84,195)					(84,195)
Preferred stock		(706)					(706)
Common stock purchases	[2]	(406,295)				(80,000)			(326,295)
Stock based compensation		17,253				3,561			13,692
Other comprehensive (loss) income, net of tax		(1,627,947)								(1,627,947)
Ending balance at Jun. 30, 2022		4,293,349		1,046	22,143	4,576,478	3,311,951		(1,665,253)	(1,953,016)
Beginning balance at Dec. 31, 2021		5,969,397		1,046	22,143	4,650,182	2,973,745		(1,352,650)	(325,069)
Increase Decrease In Stockholders Equity
Accounting Standards Update			ASU 2022-02					ASU 2022-02
Ending balance at Dec. 31, 2022		4,093,425	$ 28,752	1,047	22,143	4,790,993	3,834,348	$ 28,752	(2,030,178)	(2,524,928)
Beginning balance at Mar. 31, 2022		4,671,246		1,046	22,143	4,571,111	3,143,004		(1,668,820)	(1,397,238)
Increase Decrease In Stockholders Equity
Net income		211,421					211,421
Issuance of stock		1,536				1,536
Dividends declared:
Common stock	[3]	(42,121)					(42,121)
Preferred stock		(353)					(353)
Common stock purchases		(1,375)							(1,375)
Stock based compensation		8,773				3,831			4,942
Other comprehensive (loss) income, net of tax		(555,778)								(555,778)
Ending balance at Jun. 30, 2022		4,293,349		1,046	22,143	4,576,478	3,311,951		(1,665,253)	(1,953,016)
Beginning balance at Dec. 31, 2022		4,093,425	$ 28,752	1,047	22,143	4,790,993	3,834,348	$ 28,752	(2,030,178)	(2,524,928)
Increase Decrease In Stockholders Equity
Net income		310,139					310,139
Issuance of stock		3,117				3,117
Dividends declared:
Common stock	[1]	(79,249)					(79,249)
Preferred stock		(706)					(706)
Common stock purchases		(4,241)							(4,241)
Stock based compensation		17,279				1,471			15,808
Other comprehensive (loss) income, net of tax		196,493								196,493
Ending balance at Jun. 30, 2023		4,565,009		1,047	22,143	4,795,581	4,093,284		(2,018,611)	(2,328,435)
Beginning balance at Mar. 31, 2023		4,470,725		1,047	22,143	4,792,619	3,982,140		(2,025,399)	(2,301,825)
Increase Decrease In Stockholders Equity
Net income		151,160					151,160
Issuance of stock		1,550				1,550
Dividends declared:
Common stock	[3]	(39,663)					(39,663)
Preferred stock		(353)					(353)
Common stock purchases		(1,271)							(1,271)
Stock based compensation		9,471				1,412			8,059
Other comprehensive (loss) income, net of tax		(26,610)								(26,610)
Ending balance at Jun. 30, 2023		$ 4,565,009		$ 1,047	$ 22,143	$ 4,795,581	$ 4,093,284		$ (2,018,611)	$ (2,328,435)

[1] Dividends declared per common share during the six months   ended June 30, 2023 - $ 1.10   (2022 - $ 1.10 ).

[2] During the six months ended June 30, 2022, the Corporation   entered into a $ 400   million accelerated share repurchase transaction with   respect to its common stock, which was accounted for as a treasury   stock transaction. Refer to Note 18 for additional information.

[3] Dividends declared per common share during the quarter   ended June 30, 2023 - $ 0.55   (2022 - $ 0.55 ).