Components of Net Deferred Taxes (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 30, 2020
Deferred tax assets:
Operating lease liabilities	$ 29,115	$ 29,997
Net operating loss carryforwards	5,590	5,620
Vacation accrual	2,923	2,931
Pension accrual	3,603	3,807
Allowance for bad debts	1,291	1,653
Insurance accrual	2,020	2,283
Inventory capitalization	631	641
Fair value of derivative instruments		3,556
Other, net	1,504	1,208
Total deferred tax assets	46,677	51,696
Valuation allowance	(3,976)	(3,890)
Net deferred tax assets	42,701	47,806
Deferred tax liabilities:
Operating lease right-of-use assets	27,774	28,492
Property and equipment	14,374	14,305
Intangibles	19,591	19,091
Fair value of derivative instruments	6,864
Other, net	3,112	3,145
Total deferred tax liabilities	71,715	65,033
Net deferred taxes	$ (29,014)	$ (17,227)