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Additions made to capitalized computer software costs during the period.

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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The cash outflow associated with the development or modification of software programs or applications for internal use (that is, not to be sold, leased or otherwise marketed to others) that qualify for capitalization.

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Property, Plant and Equipment (Details) $ in Thousands	3 Months Ended	12 Months Ended			72 Months Ended
Property, Plant and Equipment (Details) $ in Thousands	Jun. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($) building	Sep. 30, 2018 USD ($)	Sep. 30, 2020 USD ($)
PROPERTY, PLANT AND EQUIPMENT
Accumulated depreciation and amortization		$ (189,394)	$ (160,271)		$ (189,394)
Property, plant and equipment - net		166,301	$ 144,969		166,301
Number of buildings \| building			2
Lease term			5 years
Proceeds from sale of property	$ 44,900		$ 44,891
Gain on sale of real estate	$ 32,500	170	32,510
Development expense		44,574	50,132	$ 52,398
Depreciation of plant and equipment and amortization of leasehold improvements		29,200	22,600	19,500
Land and land improvements
PROPERTY, PLANT AND EQUIPMENT
Property, plant and equipment, Gross		7,423	7,348		7,423
Buildings and improvements
PROPERTY, PLANT AND EQUIPMENT
Property, plant and equipment, Gross		$ 49,716	48,191		49,716
Buildings and improvements \| Minimum
PROPERTY, PLANT AND EQUIPMENT
Estimated life (years)		15 years
Buildings and improvements \| Maximum
PROPERTY, PLANT AND EQUIPMENT
Estimated life (years)		39 years
Machinery and other equipment
PROPERTY, PLANT AND EQUIPMENT
Property, plant and equipment, Gross		$ 132,962	107,297		132,962
Machinery and other equipment \| Minimum
PROPERTY, PLANT AND EQUIPMENT
Estimated life (years)		5 years
Machinery and other equipment \| Maximum
PROPERTY, PLANT AND EQUIPMENT
Estimated life (years)		10 years
Software
PROPERTY, PLANT AND EQUIPMENT
Property, plant and equipment, Gross		$ 121,890	108,526		121,890
Costs related to the purchase and development of software		1,100	3,100	22,500	140,000
Addition to capitalized software expenses		$ 1,100	1,600	7,500
Development expense			1,500	$ 15,000
Software \| Minimum
PROPERTY, PLANT AND EQUIPMENT
Estimated life (years)		3 years
Software \| Maximum
PROPERTY, PLANT AND EQUIPMENT
Estimated life (years)		7 years
Leasehold improvements
PROPERTY, PLANT AND EQUIPMENT
Property, plant and equipment, Gross		$ 22,295	17,064		22,295
Construction and internal-use software development in progress
PROPERTY, PLANT AND EQUIPMENT
Property, plant and equipment, Gross		$ 21,409	$ 16,814		$ 21,409