Revenue (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Increase in revenue related to changes in estimated total lifetime sales	$ 6,784	$ 6,017
Increase in cost of goods sold related to changes in estimated total lifetime sales	6,638	9,580
Amortized capitalized costs to fulfill contracts	1,241	376
Deferred liability revenue amortization	1,664	719
Capitalized cost	$ 133,349	105,206
Billed accounts receivable due within	60 days
Noncurrent unbilled receivables	$ 16,751	$ 1,573
Percent of total billed and unbilled accounts receivable from U.S. Government	10.00%	10.00%
Revenue from contract liabilities	$ 29,579	$ 21,658
Revenue related to noncash consideration	79,569	98,061
Aerospace [Member]
Revenue related to noncash consideration	78,179	96,762
Industrial [Member]
Revenue related to noncash consideration	$ 1,390	$ 1,299
Net Sales [Member] \| Manufactured Products [Member]
Percentage of attributable to revenue	86.00%	86.00%
Net Sales [Member] \| MRO Products [Member]
Percentage of attributable to revenue	12.00%	12.00%
Net Sales [Member] \| Service [Member]
Percentage of attributable to revenue	2.00%	2.00%

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

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Amount, before accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Consideration recognized as revenue when customers trade in used products in exchange for new or refurbished products or provide inventory to the company which will be integrated into final products sold to those customers. The company obtains control of these exchanged products and customer provided inventory.

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Percentage billed and unbilled accounts receivable from United State government

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