Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2019	Sep. 30, 2019
Income Taxes [Line Items]
Gross unrecognized tax benefits	$ 10,631	$ 10,305
Unrecognized tax benefits that, if recognized, would affect the effective tax rate	4,582
Accrued interest and penalties	$ 481	$ 437
Domestic Tax Authority [Member]
Income Taxes [Line Items]
Year remaining open to tax examination	2017
Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Year under examination	2017
State and Local Jurisdiction [Member]
Income Taxes [Line Items]
Year remaining open to tax examination	2015
Foreign Jurisdiction [Member]
Income Taxes [Line Items]
Year remaining open to tax examination	2016

Tax year being audited in the income tax examination, in CCYY format.

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Tax year that remains open to examination under enacted tax laws, in CCYY format.

+ References

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Amount of unrecognized tax benefits.

+ References

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Income Taxes [Line Items]

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