Consolidated Statement of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss
Beginning Balance at Sep. 30, 2015	$ 289,624	$ 131	$ 74,160	$ 228,278	$ (12,945)
Beginning Balance, Shares at Sep. 30, 2015		13,147,916
Net loss	(45,970)			(45,970)
Other comprehensive income (loss)	(2,996)				(2,996)
Excess tax expense from stock-based compensation	$ (1,411)		(1,411)
Issuance of restricted stock		$ 2	(2)
Issuance of restricted stock, Shares		182,400
Forfeiture of restricted stock, Shares		(2,250)
Issuance of common stock pursuant to exercise of options, Shares	0
Stock-based compensation	$ 5,220		5,220
Ending Balance at Sep. 30, 2016	244,467	$ 133	77,967	182,308	(15,941)
Ending Balance, Shares at Sep. 30, 2016		13,328,066
Net loss	(56,791)			(56,791)
Other comprehensive income (loss)	1,711				1,711
Issuance of restricted stock		$ 1	(1)
Issuance of restricted stock, Shares		109,500
Forfeiture of restricted stock, Shares		(3,250)
Issuance of common stock pursuant to exercise of options, net of tax	$ 35		35
Issuance of common stock pursuant to exercise of options, Shares	4,000	4,000
Stock-based compensation	$ 5,732		5,732
Ending Balance at Sep. 30, 2017	$ 195,154	$ 134	83,733	125,517	(14,230)
Ending Balance, Shares at Sep. 30, 2017	13,438,316	13,438,316
Cumulative adjustment for intercompany profits onintra-entity asset transfers	$ (351)			(351)
Ending Balance at Sep. 30, 2017	194,803	$ 134	83,733	125,166	(14,230)
Ending Balance, Shares at Sep. 30, 2017		13,438,316
Net loss	(19,212)			(19,212)
Other comprehensive income (loss)	(1,389)				(1,389)
Issuance of restricted stock		$ 2	(2)
Issuance of restricted stock, Shares		176,450
Forfeiture of restricted stock, Shares		(21,925)
Issuance of common stock pursuant to exercise of options, net of tax	$ 67		67
Issuance of common stock pursuant to exercise of options, Shares	7,700	7,700
Stock-based compensation	$ 2,318		2,318
Ending Balance at Sep. 30, 2018	$ 176,587	$ 136	$ 86,116	$ 105,954	$ (15,619)
Ending Balance, Shares at Sep. 30, 2018	13,600,541	13,600,541