Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Operating Activities:
Net income (loss)	$ 3,352	$ (8,691)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization	9,408	9,655
Stock-based compensation	2,220	2,485
Bad debt expense	126	110
Deferred income tax benefit	(1,023)	(2,840)
Gain on amended supply agreement	0	(507)
Changes in operating assets and liabilities:
Accounts receivable, net	(16,350)	(19,252)
Contract assets and liabilities, net	42,954	(6,211)
Inventories	(8,202)	(4,542)
Income taxes	6,439	945
Prepaid expenses and other current assets	(1,330)	924
Accounts payable	(2,174)	1,288
Accrued liabilities	(3,051)	355
Other, net	1,566	224
Net cash provided by (used in) operating activities	33,935	(26,057)
Investing Activities:
Purchases of short-term investments	(5,869)	(20,712)
Maturities of short-term investments	13,088	31,444
Purchases of property, plant and equipment, net	(3,210)	(3,922)
Net cash provided by investing activities	4,009	6,810
Financing Activities:
Payments on industrial development revenue bonds	(400)	(400)
Shares withheld in lieu of employee tax withholding	(1,151)	(578)
Dividends paid	(8,991)	(8,934)
Net cash used in financing activities	(10,542)	(9,912)
Net increase (decrease) in cash, cash equivalents and restricted cash	27,402	(29,159)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(542)	(389)
Cash, cash equivalents and restricted cash, beginning of period	61,725	93,210
Cash, cash equivalents and restricted cash, end of period	$ 88,585	$ 63,662