Leases (Lease-Related Assets and Liabilities) (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Sep. 30, 2022
Assets:
Operating lease assets	$ 24,680	$ 25,144
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other assets	Other assets
Finance lease assets	$ 3,337	$ 5,474
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Property, plant and equipment, net	Property, plant and equipment, net
Total lease assets	$ 28,017	$ 30,618
Current liabilities:
Operating lease liabilities	$ 4,594	$ 4,587
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Accrued liabilities	Accrued liabilities
Finance lease liabilities	$ 817	$ 856
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Current portion of long-term debt	Current portion of long-term debt
Noncurrent liabilities:
Operating lease liabilities	$ 20,685	$ 21,443
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other liabilities	Other liabilities
Finance lease liabilities	$ 2,733	$ 4,405
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Long-term debt, less current portion	Long-term debt, less current portion
Total lease liabilities	$ 28,829	$ 31,291