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Stock-Based Compensation - Nonvested Performance-based Award Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Non-Employee Directors \| Deferred compensation plans and restricted share awards
Non-vested PSU Awards [Roll Forward]
Granted at target level (in shares)	6,160	4,827
Non-vested PSU Awards, Weighted Average Fair Value [Roll Forward]
Granted at target level (in dollars per share)	$ 357.00	$ 300.78
Stock-settled PSU awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of shares to be issued upon conversion (in shares)	36,080
Average remaining term of shares issued at conversion	1 year
Non-vested PSU Awards [Roll Forward]
Outstanding, beginning (in shares)	112,553
Granted at target level (in shares)	37,736
Adjustments above/(below) target (in shares)	47,154
Vested and converted (in shares)	(93,902)
Forfeited (in shares)	(5,100)
Outstanding, ending (in shares)	98,441	112,553
Non-vested PSU Awards, Weighted Average Fair Value [Roll Forward]
Outstanding, beginning (in dollars per share)	$ 278.38
Granted at target level (in dollars per share)	306.97	$ 362.40	$ 333.58
Adjustments above/(below) target (in dollars per share)	181.31
Vested and converted (in dollars per share)	306.68
Forfeited (in dollars per share)	317.85
Outstanding, ending (in dollars per share)	$ 334.03	$ 278.38
Stock-settled PSU awards \| Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Actual payout range	0.00%
Stock-settled PSU awards \| Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Actual payout range	200.00%
Performance share units, cash-settled
Non-vested PSU Awards [Roll Forward]
Outstanding, beginning (in shares)	890
Granted at target level (in shares)	82
Adjustments above/(below) target (in shares)	591
Vested and converted (in shares)	(1,181)
Forfeited (in shares)	(178)
Outstanding, ending (in shares)	204	890
Non-vested PSU Awards, Weighted Average Fair Value [Roll Forward]
Outstanding, beginning (in dollars per share)	$ 242.29
Granted at target level (in dollars per share)	306.68
Adjustments above/(below) target (in dollars per share)	191.43
Vested and converted (in dollars per share)	306.68
Forfeited (in dollars per share)	310.52
Outstanding, ending (in dollars per share)	$ 355.74	$ 242.29
Restricted Stock
Non-vested PSU Awards [Roll Forward]
Granted at target level (in shares)	8,343	9,648	6,002
Non-vested PSU Awards, Weighted Average Fair Value [Roll Forward]
Granted at target level (in dollars per share)	$ 314.06	$ 310.52	$ 312.41