Pension Plans - Fair Value of Plan Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Fair Value of Plan Assets [Line Items]
Fair value of plan assets	$ 67,581	$ 78,385
Government
Fair Value of Plan Assets [Line Items]
Fair value of plan assets	20,430	24,013
Corporate Investment Grade
Fair Value of Plan Assets [Line Items]
Fair value of plan assets	2,038	2,924
Large Capitalization Stocks
Fair Value of Plan Assets [Line Items]
Fair value of plan assets	22,379	27,078
Commodity Option
Fair Value of Plan Assets [Line Items]
Fair value of plan assets	599	8,558
Insurance Company Funds
Fair Value of Plan Assets [Line Items]
Fair value of plan assets	6,823	9,105
Options
Fair Value of Plan Assets [Line Items]
Fair value of plan assets	1,430	1,122
Cash
Fair Value of Plan Assets [Line Items]
Fair value of plan assets	13,882	5,585
Level 1
Fair Value of Plan Assets [Line Items]
Fair value of plan assets	60,758	69,280
Level 1 | Government
Fair Value of Plan Assets [Line Items]
Fair value of plan assets	20,430	24,013
Level 1 | Corporate Investment Grade
Fair Value of Plan Assets [Line Items]
Fair value of plan assets	2,038	2,924
Level 1 | Large Capitalization Stocks
Fair Value of Plan Assets [Line Items]
Fair value of plan assets	22,379	27,078
Level 1 | Commodity Option
Fair Value of Plan Assets [Line Items]
Fair value of plan assets	599	8,558
Level 1 | Options
Fair Value of Plan Assets [Line Items]
Fair value of plan assets	1,430	1,122
Level 1 | Cash
Fair Value of Plan Assets [Line Items]
Fair value of plan assets	13,882	5,585
Level 2
Fair Value of Plan Assets [Line Items]
Fair value of plan assets	6,823	9,105
Level 2 | Insurance Company Funds
Fair Value of Plan Assets [Line Items]
Fair value of plan assets	$ 6,823	$ 9,105