Derivative Instruments and Hedging Activities - Gains and losses recognized (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Derivative instruments and hedging activities
Estimated unrealized net gains (losses) from cash flow hedges which are expected to be reclassified into earnings in the next twelve months	$ 700
Foreign currency forwards
Derivative instruments and hedging activities
Gains (losses) recognized in OCI	(1,583)	$ 1,779
Gains (losses) reclassified into earnings - Effective Portion	$ (66)	$ (33)

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No definition available.

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The estimated net amount of unrealized gains or losses on foreign currency cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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Amount before tax of reclassification adjustments of other comprehensive income (loss).

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