Fair Value Measurements - Assets Measured at Fair Value on Recurring Basis (Details) - Recurring [Member] - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Equity Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value assets	$ 911	$ 5,150
Equity Mutual Fund [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value assets	15,945	9,523
Commodity Mutual Fund [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value assets	188	249
Derivative Contract Asset [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value assets	26	1,245
U.S. Treasury Mutual Funds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value assets	12,942	12,889
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Equity Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value assets	911	416
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Derivative Contract Asset [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value assets	26	1,245
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | U.S. Treasury Mutual Funds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value assets	12,942	12,889
Significant Other Observable Inputs (Level 2) [Member] | Equity Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value assets		4,734
Significant Other Observable Inputs (Level 2) [Member] | Equity Mutual Fund [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value assets	15,945	9,523
Significant Other Observable Inputs (Level 2) [Member] | Commodity Mutual Fund [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value assets	$ 188	$ 249