The Incentive Stock Plans - Summary of Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Sep. 30, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options granted, Options Outstanding	0	0
Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares Available for Grant, Beginning Balance	1,275,415
Options cancelled/forfeited/expired, Shares Available for Grant	10,000
Restricted stock awards issued, Shares Available for Grant	(336,591)
Restricted stock awards forfeited, Shares Available for Grant	5,975
Additional shares of stock issued, Shares Available for Grant	(3,374)
Shares Available for Grant, Ending Balance	951,425		1,275,415
Options Outstanding, Beginning Balance	196,329
Options cancelled/forfeited/expired, Options Outstanding	(10,000)
Options exercised, Options Outstanding	(71,079)
Options Outstanding, Ending Balance	115,250		196,329
Exercisable as of March 31, 2021, Options Outstanding	115,250
Aggregate Intrinsic Value	$ 4,531		$ 2,636
Exercisable as of March 31 2021, Aggregate Intrinsic Value	$ 4,531
Weighted Average Exercise Price, Beginning Balance	$ 12.12
Weighted Average Exercise Price, Ending Balance	11.66		$ 12.12
Exercisable as of March 31 2021, Weighted Average Exercise Price	$ 11.66
Weighted Average Remaining Contractual Life	2 years 2 months 12 days		2 years 6 months
Exercisable as of March 31, 2021, Weighted Average Remaining Contractual Life	2 years 2 months 12 days