Stock-Based Compensation Plans - Nonvested Performance Awards Granted (Details) - Performance awards - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Performance awards
Outstanding at the beginning of the period (in shares)	279,067	284,522	241,921
Granted (in shares)	90,215	72,783	138,033
Increase (decrease) in awards based on performance (in shares)	(31,345)	(20,356)	(37,469)
Converted to restricted stock (in shares)			(56,545)
Converted to shares of common stock (in shares)	(60,016)	(54,053)	(56,545)
Forfeited (in shares)	(2,719)	(3,829)	(1,418)
Outstanding at the ending of the period (in shares)	275,202	279,067	284,522
Weighted average grant date fair value per award
Outstanding at the beginning of the period (in dollars per share)	$ 225.46	$ 214.73	$ 195.13
Granted (in dollars per share)	193.85	254.75	191.12
Change in awards based on performance (in dollars per share)	241.49	200.92	156.00
Converted to restricted stock (in dollars per share)			156.00
Converted to common stock (in dollars per share)	238.71	217.33
Forfeited (in dollars per share)	212.05	230.36	207.65
Outstanding at the ending of the period (in dollars per share)	$ 210.52	$ 225.46	$ 214.73
Grants in period based on shareholder metrics (in shares)	49,611	39,972	69,064
Grants in period based on financial metrics (in shares)	40,604	32,811	68,969