Stock Option Plans - Assumptions Used to Value Option Grants (Details)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected life in years	7 years	7 years
Interest rate	3.85%	4.17%
Volatility	0.455%	0.422%
Dividend yield	1.5	1.8