Income Taxes - Rate (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Effective income tax rate reconciliation
Statutory federal tax rate (as a percent)	21.00%	24.53%	35.00%	35.00%
Tax provision for income taxes at the statutory rate		$ (1,059)	$ (6,026)	$ 1,313
Foreign tax rate differentials		(685)	(1,103)	(1,505)
Provision for state taxes, net of federal taxes		(45)	(371)	778
U.S. tax on distributed and undistributed earnings of foreign subsidiaries		240	452	523
Manufacturer's deduction		(86)		(98)
Tax credits		(511)	(409)	(1,198)
Transition tax		2,170
State tax rate change impact on deferred tax asset		16,633	192	(1,819)
Net operating loss carryback		407
Change in valuation allowance		475	195	408
Other, net		158	43	329
Total provision for (benefit from) income taxes		$ 17,697	$ (7,027)	$ (1,269)
Effective tax rate (as a percent)		(436.50%)	40.80%	(33.80%)

The portion of the difference, between total income tax expense or benefit as reported in the income statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to distributed and undistributed earnings (losses) of foreign subsidiaries.

No definition available.