Income Taxes - Reconciliation of Income Tax Expense (Benefit) Attributable to Income from Operations (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Reconciliation of income tax expense reported to amount computed by applying the U.S. federal tax rate
Provision for income taxes at the statutory federal rate	$ 33,598	$ 25,786
Increase (reduction) in taxes resulting from:
Excess tax benefit on share-based compensation	(1,874)	(1,990)
Tax exempt interest income	(260)	(283)
Dividends received deduction	(235)	(224)
Tax credit	(768)	(513)
ESOP dividends paid deduction	(138)	(137)
Nondeductible expenses	713	601
Other items, net	1,055	740
Income tax expense	$ 32,091	$ 23,980
Reconciliation of income tax expense rate to the U.S. federal tax rate
Tax rate used (as a percent)	21.00%	21.00%
Excess tax benefit on share-based compensation (as a percent)	(1.20%)	(1.60%)
Effective rate reduction due to tax exempt interest income (as a percent)	(0.20%)	(0.20%)
Effective rate reduction due to dividend received (as a percent)	(0.10%)	(0.20%)
Effective rate reduction due to tax credit (as a percent)	(0.50%)	(0.40%)
Effective rate reduction due to dividend paid to ESOP (as a percent)	(0.10%)	(0.10%)
Effective rate reduction due to nondeductible expenses (as a percent)	0.40%	0.50%
Effective rate reduction due to other items, net (as a percent)	0.80%	0.50%
Total tax expense	20.10%	19.50%