CONDENSED CONSOLIDATED STATEMENT OF SHAREHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	COMMON STOCK	CAPITAL IN EXCESS OF PAR VALUE	RETAINED EARNINGS	TREASURY SHARES	ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	DEFERRED COMPENSATION
Beginning balance (in shares) at Sep. 30, 2022		84,746
Beginning balance (in shares) at Sep. 30, 2022					27,682
Balance at Sep. 30, 2022	$ 477,570	$ 21,187	$ 627,982	$ 344,060	$ (420,116)	$ (82,738)	$ (12,805)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	48,702			48,702
Dividend	(6,145)			(6,145)
Shares withheld on employee taxes on vested equity awards (in shares)					345
Shares withheld on employee taxes on vested equity awards	(12,734)				$ (12,734)
Amortization of deferred compensation	571						571
Equity awards granted, net (in shares)					(467)
Equity awards granted, net	0		(7,082)		$ 7,082
ESOP allocation of common stock	1,127		1,127
Stock-based compensation	5,538		5,538
Other comprehensive income, net of tax	12,219					12,219
Ending balance (in shares) at Dec. 31, 2022		84,746
Ending balance (in shares) at Dec. 31, 2022					27,560
Balance at Dec. 31, 2022	526,848	$ 21,187	627,565	386,617	$ (425,768)	(70,519)	(12,234)
Beginning balance (in shares) at Sep. 30, 2023		84,746
Beginning balance (in shares) at Sep. 30, 2023					31,684
Balance at Sep. 30, 2023	315,244	$ 21,187	662,680	281,516	$ (577,686)	(70,010)	(2,443)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	42,177			42,177
Dividend	(7,825)			(7,825)
Shares withheld on employee taxes on vested equity awards (in shares)					221
Shares withheld on employee taxes on vested equity awards	(11,604)				$ (11,604)
Amortization of deferred compensation	520						520
Common stock acquired (in shares)					1,634
Common stock acquired	(70,543)				$ (70,543)
Equity awards granted, net (in shares)					(180)
Equity awards granted, net	0		(3,383)		$ 3,383
ESOP allocation of common stock	1,550		1,550
Stock-based compensation	5,028		5,028
Other comprehensive income, net of tax	10,475					10,475
Ending balance (in shares) at Dec. 31, 2023		84,746
Ending balance (in shares) at Dec. 31, 2023					33,359
Balance at Dec. 31, 2023	$ 285,022	$ 21,187	$ 665,875	$ 315,868	$ (656,450)	$ (59,535)	$ (1,923)