Fair Value of Financial Instruments - Recurring Basis (Details) - Assets and liabilities measured at fair value - USD ($) $ in Thousands	Dec. 31, 2019	Sep. 30, 2019
Assets
Current derivative assets	$ 930	$ 2,635
Noncurrent derivative assets	1,873	859
Total assets measured at fair value	2,803	3,494
Liabilities
Current derivative liabilities	1,855	529
Noncurrent derivative liabilities	272	228
Total liabilities measured at fair value	9,996	11,631
Deltenna
Liabilities
Contingent consideration to seller	3,000	1,787
Shield Aviation
Liabilities
Contingent consideration to seller	4,041	3,814
H4 Global
Liabilities
Contingent consideration to seller	828	1,073
Nuvotronics
Liabilities
Contingent consideration to seller		4,200
Level 2
Assets
Current derivative assets	930	2,635
Noncurrent derivative assets	1,873	859
Total assets measured at fair value	2,803	3,494
Liabilities
Current derivative liabilities	1,855	529
Noncurrent derivative liabilities	272	228
Total liabilities measured at fair value	2,127	757
Level 3
Liabilities
Total liabilities measured at fair value	7,869	10,874
Level 3 \| Deltenna
Liabilities
Contingent consideration to seller	3,000	1,787
Level 3 \| Shield Aviation
Liabilities
Contingent consideration to seller	4,041	3,814
Level 3 \| H4 Global
Liabilities
Contingent consideration to seller	$ 828	1,073
Level 3 \| Nuvotronics
Liabilities
Contingent consideration to seller		$ 4,200

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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