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
Balance (in shares) at Sep. 30, 2018		81,520			35,846
Balance at Sep. 30, 2018	$ 474,391	$ 20,380	$ 503,396	$ 550,523	$ (534,830)	$ (34,112)	$ (30,966)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	8,753			8,753
Dividend	(3,143)			(3,143)
Shares withheld on employee taxes on vested equity awards (in shares)					83
Shares withheld on employee taxes on vested equity awards	(1,058)				$ (1,058)
Amortization of deferred compensation	856						856
Common stock acquired (in shares)					29
Common stock acquired	(290)				$ (290)
Equity awards granted, net (in shares)		1,201
Equity awards granted, net	0	$ 300	(300)
ESOP allocation of common stock	(8)		(8)
Stock-based compensation	2,933		2,933
Stock-based consideration	250		250
Other comprehensive income, net of tax	(5,450)					(5,450)
Balance (in shares) at Dec. 31, 2018		82,721			35,958
Balance at Dec. 31, 2018	471,561	$ 20,680	506,271	550,460	$ (536,178)	(39,562)	(30,110)
Balance (in shares) at Sep. 30, 2018		81,520			35,846
Balance at Sep. 30, 2018	474,391	$ 20,380	503,396	550,523	$ (534,830)	(34,112)	(30,966)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	7,597
Other comprehensive income, net of tax	(2,570)
Balance (in shares) at Mar. 31, 2019		82,769			35,969
Balance at Mar. 31, 2019	474,284	$ 20,692	510,585	545,600	$ (536,308)	(36,682)	(29,603)
Balance (in shares) at Dec. 31, 2018		82,721			35,958
Balance at Dec. 31, 2018	471,561	$ 20,680	506,271	550,460	$ (536,178)	(39,562)	(30,110)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(1,156)			(1,156)
Dividend	(3,704)			(3,704)
Shares withheld on employee taxes on vested equity awards (in shares)					3
Shares withheld on employee taxes on vested equity awards	(48)				$ (48)
Amortization of deferred compensation	507						507
Common stock acquired (in shares)					8
Common stock acquired	(82)				$ (82)
Equity awards granted, net (in shares)		48
Equity awards granted, net	0	$ 12	(12)
ESOP allocation of common stock	601		601
Stock-based compensation	3,422		3,422
Stock-based consideration	303		303
Other comprehensive income, net of tax	2,880					2,880
Balance (in shares) at Mar. 31, 2019		82,769			35,969
Balance at Mar. 31, 2019	474,284	$ 20,692	510,585	545,600	$ (536,308)	(36,682)	(29,603)
Balance (in shares) at Sep. 30, 2019		82,775			35,969
Balance at Sep. 30, 2019	477,763	$ 20,694	519,017	568,516	$ (536,308)	(65,916)	(28,240)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	10,612			10,612
Dividend	(3,392)			(3,392)
Shares withheld on employee taxes on vested equity awards (in shares)					80
Shares withheld on employee taxes on vested equity awards	(1,758)				$ (1,758)
Amortization of deferred compensation	629						629
Equity awards granted, net (in shares)		182
Equity awards granted, net	0	$ 45	(45)
ESOP allocation of common stock	609		609
Stock-based compensation	3,150		3,150
Stock-based consideration	239		239
Other comprehensive income, net of tax	6,841					6,841
Balance (in shares) at Dec. 31, 2019		82,957			36,049
Balance at Dec. 31, 2019	494,693	$ 20,739	522,970	575,736	$ (538,066)	(59,075)	(27,611)
Balance (in shares) at Sep. 30, 2019		82,775			35,969
Balance at Sep. 30, 2019	477,763	$ 20,694	519,017	568,516	$ (536,308)	(65,916)	(28,240)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	11,507
Other comprehensive income, net of tax	(7,993)
Balance (in shares) at Mar. 31, 2020		83,741			36,310
Balance at Mar. 31, 2020	476,454	$ 20,935	526,988	573,209	$ (543,787)	(73,909)	(26,982)
Balance (in shares) at Dec. 31, 2019		82,957			36,049
Balance at Dec. 31, 2019	494,693	$ 20,739	522,970	575,736	$ (538,066)	(59,075)	(27,611)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	895			895
Dividend	(3,422)			(3,422)
Shares withheld on employee taxes on vested equity awards (in shares)					261
Shares withheld on employee taxes on vested equity awards	(5,721)				$ (5,721)
Amortization of deferred compensation	629						629
Equity awards granted, net (in shares)		784
Equity awards granted, net	0	$ 196	(196)
ESOP allocation of common stock	435		435
Stock-based compensation	3,662		3,662
Stock-based consideration	117		117
Other comprehensive income, net of tax	(14,834)					(14,834)
Balance (in shares) at Mar. 31, 2020		83,741			36,310
Balance at Mar. 31, 2020	$ 476,454	$ 20,935	$ 526,988	$ 573,209	$ (543,787)	$ (73,909)	$ (26,982)