Other Comprehensive Income (Loss) - Pretax and Related Income Tax Benefit (Expense) Components (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Amounts Reclassified From Accumulated Other Comprehensive Income [Abstract]
Total reclassifications	$ 1,090,034	$ 801,777	$ 559,263
Income tax benefit (expense)	(224,685)	(166,794)	(113,170)
Net income	865,349	634,983	446,093
Reclassification from Accumulated Other Comprehensive Income
Amounts Reclassified From Accumulated Other Comprehensive Income [Abstract]
Total reclassifications	(26,610)	676	(2,106)
Income tax benefit (expense)	5,588	(142)	441
Net income	(21,022)	534	(1,665)
Reclassification from Accumulated Other Comprehensive Income | Net unrealized gains and losses on available-for-sale securities
Amounts Reclassified From Accumulated Other Comprehensive Income [Abstract]
Total reclassifications	(9,860)	10,455	13,862
Income tax benefit (expense)	2,070	(2,195)	(2,912)
Net income	(7,790)	8,260	10,950
Reclassification from Accumulated Other Comprehensive Income | Net benefit plan assets and obligations recognized in shareholders' equity
Amounts Reclassified From Accumulated Other Comprehensive Income [Abstract]
Total reclassifications	(16,750)	(9,779)	(15,968)
Income tax benefit (expense)	3,518	2,053	3,353
Net income	$ (13,232)	$ (7,726)	$ (12,615)