Summary of Significant Accounting Policies (Narrative) (Details)	3 Months Ended		12 Months Ended
	Sep. 30, 2023 USD ($) customer	Sep. 30, 2022 USD ($) customer	Jun. 30, 2023 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Accounts receivable - trade	$ 0		$ 0
Reserve for loss on contract	0		0
Revenue recognized	50,000	$ 0
Contract assets	0		0
Contract liabilities	$ 0		0
Revenue recognized included in contract liabilities		56,000
Lease, Practical Expedients, Package [true false]	false
Investments in debt securities	$ 0		0
Inventory	0		0
Research and development expense	$ 0	3,062,000
Dividend rate	0.00%
Amount in excess of insured limit	$ 4,100,000		$ 6,900,000
Revenue reported in discontinued operations		$ 56,000
Revenues	$ 50,000
One Customer [Member] | Revenue [Member] | Customer Concentration Risk [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of major customers | customer	1	1
Revenue reported in discontinued operations	$ 0
Concentration risk, percentage		100.00%
Revenues		$ 0
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Fixed assets, useful life	3 years
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Fixed assets, useful life	39 years
Intellectual Property [Member]
Summary Of Significant Accounting Policies [Line Items]
Intangible asset, useful life	20 years