Accrued Expenses and Other Current Liabilities (Severance and Restructuring Accruals) (Narrative) (Details)		1 Months Ended				3 Months Ended	6 Months Ended		12 Months Ended
	Jun. 07, 2016 USD ($)	Mar. 31, 2017 USD ($) employee	Nov. 30, 2016 employee	May 31, 2016 employee	Dec. 31, 2015 USD ($)	Mar. 31, 2017 USD ($)	Mar. 31, 2017 USD ($) employee	Mar. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)
Payables and Accruals [Line Items]
Payments to terminate lease agreement								$ 200,000
Employee Severance [Member]
Payables and Accruals [Line Items]
Restructuring costs						$ 500,000
Chief Financial Officer [Member]
Payables and Accruals [Line Items]
Continuation of base salary period	448 days
Outplacement services, period	1 year
Outplacement services, value	$ 15,000
Estimated charge related to separation agreement							$ 400,000
Discontinued Operations, Disposed of by Sale [Member]
Payables and Accruals [Line Items]
Payments to terminate lease agreement					$ 200,000
Gain on lease termination								$ 300,000
Satellite Communications Assembly Operations [Member]
Payables and Accruals [Line Items]
Number of positions eliminated | employee			5	30
Satellite Communications Assembly Operations [Member] | Employee Severance [Member]
Payables and Accruals [Line Items]
Restructuring costs							$ 200,000		$ 300,000
Water Fabrication Lab [Member]
Payables and Accruals [Line Items]
Number of positions eliminated | employee		14					265
Water Fabrication Lab [Member] | Employee Severance [Member]
Payables and Accruals [Line Items]
Restructuring costs		$ 100,000					$ 500,000