Condensed Consolidated Statement of Changes Shareholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)
Balance at beginning of period (in shares) at Sep. 30, 2018		47,080
Balance at beginning of period at Sep. 30, 2018	$ 122,059	$ 472	$ (2,580)	$ 457,978	$ (317,373)	$ (16,438)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	26,949				26,949
Other comprehensive (loss) income	(2,721)					(2,721)
Stock-based compensation	2,982			2,982
Issuance of common stock (in shares)		131
Issuance of common stock	(695)	$ 1		(696)
Repurchase of common stock (in shares)		(1,230)
Repurchase of common stock	(24,419)	$ (12)			(24,407)
Balance at end of period (in shares) at Dec. 28, 2018		45,981
Balance at end of period at Dec. 28, 2018	124,155	$ 461	(2,580)	460,264	(314,831)	(19,159)
Balance at beginning of period (in shares) at Sep. 30, 2019		46,955
Balance at beginning of period at Sep. 30, 2019	232,936	$ 471	(2,580)	477,139	(200,396)	(41,698)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	34,790				34,790
Other comprehensive (loss) income	5,316					5,316
Stock-based compensation	3,123			3,123
Issuance of common stock (in shares)		524
Issuance of common stock	(2,981)	$ 5		(2,986)
Balance at end of period (in shares) at Dec. 27, 2019		47,479
Balance at end of period at Dec. 27, 2019	$ 272,131	$ 476	$ (2,580)	$ 477,276	$ (166,659)	$ (36,382)