Discontinued Operations (Income Statements) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Photovoltaics Business [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue			$ 12,614
Cost of revenue			8,245
Gross profit			4,369
Operating expense (income)			2,240
Gain on sale of discontinued operations			86,958
Other income			779
Income from discontinued operations, net of tax			61,166
Digital Products Business [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue			11,944
Cost of revenue			9,107
Gross profit			2,837
Operating expense (income)			2,800
Gain on sale of discontinued operations			1,994
Other income			0
Income from discontinued operations before income tax expense			2,031
Income tax benefit (expense)			2,175
Income from discontinued operations, net of tax			4,206
Discontinued Operations, Disposed of by Sale [Member] | Photovoltaics Business [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue	$ 0	$ 0
Cost of revenue	12	(159)
Gross profit	(12)	159
Operating expense (income)	13	(868)
Gain on sale of discontinued operations	0	0
Other income	0	0
Income from discontinued operations before income tax expense	(25)	1,027	89,866
Income tax benefit (expense)	0	20	(28,700)
Income from discontinued operations, net of tax	(25)	1,047
Discontinued Operations, Disposed of by Sale [Member] | Digital Products Business [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue	0	0
Cost of revenue	0	(500)
Gross profit	0	500
Operating expense (income)	2	(292)
Recognition of previously deferred gain on sale of assets	0	3,804	$ 0
Gain on sale of discontinued operations	0	0
Other income	41	0
Income from discontinued operations before income tax expense	39	4,596
Income tax benefit (expense)	0	4
Income from discontinued operations, net of tax	$ 39	$ 4,600