Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities:
Net income	$ 987	$ 56,128
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion expense	506	1,234
Stock-based compensation expense	387	2,608
Deferred income taxes	0	24,080
Gain on sale of Photovoltaics Business	0	(87,022)
Provision adjustments related to doubtful accounts	4	290
Provision adjustments related to product warranty	146	402
Change in fair value of financial instruments	0	(36)
Gain from change in estimate on ARO obligation	0	(845)
Reclassification of foreign currency translation adjustment	0	(744)
Gain on settlement of solar power assets and obligations	(689)	0
Gain on settlement of Newark lease	(310)	0
Net loss on disposal of equipment	0	237
Total non-cash adjustments	44	(59,796)
Changes in operating assets and liabilities:
Accounts receivable	2,877	5,334
Inventory	2,115	(2,188)
Other assets	1,439	(4,066)
Accounts payable	(43)	(374)
Accrued expenses and other current liabilities	(1,686)	7,711
Total change in operating assets and liabilities	4,702	6,417
Net cash provided by operating activities	5,733	2,749
Cash flows from investing activities:
Proceeds from sale of Photovoltaics Business	0	150,000
Purchase of equipment	(1,677)	(845)
Deposits on equipment orders	0	0
(Increase) decrease in restricted cash	(728)	1,075
Proceeds from disposal of property, plant and equipment	0	50
Net cash (used in) provided by investing activities	(2,405)	150,280
Cash flows from financing activities:
Payments on credit facilities	0	(26,518)
Proceeds from stock plans	186	355
Net cash provided by (used in) financing activities	186	(26,163)
Effect of exchange rate changes on foreign currency	121	23
Net increase in cash and cash equivalents	3,635	126,889
Cash and cash equivalents at beginning of period	111,885	20,687
Cash and cash equivalents at end of period	115,520	147,576
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Cash paid during the period for interest	23	94
Cash paid during the period for income taxes	108	25
NON-CASH INVESTING AND FINANCING ACTIVITIES
Changes in accounts payable related to purchases of equipment	$ (206)	$ 0