Fair Value of Financial Instruments - Recurring Basis (Details) - Assets and liabilities measured at fair value - USD ($) $ in Thousands	Sep. 30, 2019	Sep. 30, 2018
Assets
Cash equivalents		$ 9,000
Current derivative assets	$ 2,635	1,803
Noncurrent derivative assets	859	314
Total assets measured at fair value	3,494	11,117
Liabilities
Current derivative liabilities	529	1,657
Noncurrent derivative liabilities	228	75
Total liabilities measured at fair value	11,631	10,846
Deltenna
Liabilities
Contingent consideration to seller	1,787	1,081
Shield Aviation
Liabilities
Contingent consideration to seller	3,814	5,618
H4 Global
Liabilities
Contingent consideration to seller	1,073	665
Nuvotronics
Liabilities
Contingent consideration to seller	4,200
Revenue Targets \| TeraLogics
Liabilities
Contingent consideration to seller		1,750
Level 1
Assets
Cash equivalents		9,000
Total assets measured at fair value		9,000
Level 2
Assets
Current derivative assets	2,635	1,803
Noncurrent derivative assets	859	314
Total assets measured at fair value	3,494	2,117
Liabilities
Current derivative liabilities	529	1,657
Noncurrent derivative liabilities	228	75
Total liabilities measured at fair value	757	1,732
Level 3
Liabilities
Total liabilities measured at fair value	10,874	9,114
Level 3 \| Deltenna
Liabilities
Contingent consideration to seller	1,787	1,081
Level 3 \| Shield Aviation
Liabilities
Contingent consideration to seller	3,814	5,618
Level 3 \| H4 Global
Liabilities
Contingent consideration to seller	1,073	665
Level 3 \| Nuvotronics
Liabilities
Contingent consideration to seller	$ 4,200
Level 3 \| Revenue Targets \| TeraLogics
Liabilities
Contingent consideration to seller		$ 1,750

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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