Accounts Receivable (Allowance for Doubtful Accounts Rollforward) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance at beginning of period	$ 13	$ 103	$ 36	$ 462
Provision adjustment - expense, net of recoveries	0	16	7	20
Write-offs and other adjustments - deductions to receivable balances	(6)	(66)	(36)	(429)
Balance at end of period	$ 7	$ 53	$ 7	$ 53