Income Taxes - Reconciliation of Effective Income Tax Rate (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Reconciliation of the applicable statutory U.S. income tax rate to the effective tax rate
Statutory U.S. federal tax rate	21.00%	21.00%	21.00%
Increase/(decrease) in tax rate resulting from:
U.S. state and local income taxes, net of U.S. federal income tax benefit	2.80%	3.50%	3.00%
Tax-exempt income	(0.90%)	(0.90%)	(0.90%)
Non-U.S. earnings	1.50%	0.40%	0.10%
Business tax credits	(4.40%)	(5.40%)	(4.20%)
Other, net	(0.40%)	(0.20%)	(0.10%)
Effective tax rate	19.60%	18.40%	18.90%