Goodwill and Other Intangible Assets - Additional Information (Detail) $ in Thousands		12 Months Ended
Jul. 01, 2015 segment	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of other intangibles		$ 337
Number of reporting units \| segment	3
Impairment of goodwill		10,423
Impairment of intangible assets		1,400
Goodwill		$ 0	$ 10,455

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

+ References

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Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

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