Employee Stock and Incentive Plans - Performance Shares and Restricted Stock Units (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Performance Shares
Number of Shares
As of January 1	60,489	80,661	85,284
Granted (in shares)	54,039	37,731	33,304
Awarded (in shares)	0	0	0
Unearned Grant Award (in shares)	0	(50,524)	(33,375)
Forfeited (in shares)	(3,030)	(7,379)	(4,552)
As of December 31	111,498	60,489	80,661
Weighted- Average Grant Date Fair Value
As of January 1	$ 69.62	$ 75.80	$ 80.73
Granted	63.50	67.22	73.25
Awarded	0	0	0
Unearned Grant Award	0	77.49	86.09
Forfeited	67.60	71.00	74.05
As of December 31	$ 66.71	$ 69.62	$ 75.80
Restricted Stock Units
Number of Shares
As of January 1	33,564	28,141	37,482
Granted (in shares)	21,200	15,477	16,251
Awarded (in shares)	(9,631)	(7,396)	(23,631)
Forfeited (in shares)	(1,389)	(2,658)	(1,961)
As of December 31	43,744	33,564	28,141
Weighted- Average Grant Date Fair Value
As of January 1	$ 68.80	$ 73.16	$ 77.64
Granted	61.16	63.70	64.97
Awarded	81.91	75.55	74.53
Forfeited	63.46	66.44	74.52
As of December 31	$ 62.38	$ 68.80	$ 73.16