Stock-Based Compensation - Summary of Restricted Stock and Restricted Stock Units Granted (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)	166,202	156,789	161,909
Directors Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)	10,746	10,031	4,548
Price per share (in dollars per share)	$ 94.94	$ 92.40	$ 105.56
Aggregate value	$ 1,020	$ 927	$ 480
Percent vested	100.00%	97.00%	100.00%
Directors Restricted Stock Units Including Dividend Equivalents
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)	8,956	7,258	6,161
Price per share (in dollars per share)	$ 95.62	$ 92.60	$ 103.32
Aggregate value	$ 856	$ 672	$ 637
Percent vested	100.00%	96.00%	100.00%
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)	146,500	139,500	151,200
Price per share (in dollars per share)	$ 103.23	$ 98.32	$ 100.74
Aggregate value	$ 15,123	$ 13,716	$ 15,232
Percent vested	0.00%	0.00%	0.00%

Restricted Stock And Restricted Stock Units Granted, Vested Percentage

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Aggregate value of stock related to Restricted Stock Awards issued during the period.

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