Long-Term Debt and Bank Facility Borrowings - Company's Debt (Detail) - USD ($) $ in Thousands		Dec. 31, 2021	Sep. 30, 2021
Debt Instrument [Line Items]
Long-term debt, carrying Amount		$ 225,865	$ 118,624
Current maturities of long-term debt, carrying Amount		136,682	26,239
Long-term debt		89,183	92,385
Long-term debt, fair value	[1]	226,311	119,118
Current maturities of long-term debt, fair value	[1]	136,682	26,239
Long-term portion of debt, fair value	[1]	89,629	92,879
Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility borrowings, carrying Amount		123,682	8,618
Credit facility borrowings, fair value	[1]	123,682	8,618
Term Loan
Debt Instrument [Line Items]
Long-term debt, carrying Amount	[2]	102,183	110,006
Long-term debt, fair value	[1],[2]	$ 102,629	$ 110,500

[1] The face amount of the Company’s variable rate long-term debt approximates fair value.

[2] Carrying amounts are net of unamortized debt issuance costs of $0.4 million as of December 31, 2021 and $0.5 million as of September 30, 2021.