Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 30, 2020
Deferred tax assets:
Tax credit carryforwards	$ 177,611	$ 192,981
Inventory adjustments	25,174	34,971
Incentive compensation	13,793	13,116
Intangible assets	6,016	13,993
Warranty and other reserves	6,006	5,503
Property, equipment and other assets	2,085	2,197
Uncertain tax positions	705	723
Other	2,435	844
Total deferred tax assets	233,825	264,328
Valuation allowance	(29,059)	(39,185)
Deferred tax assets, net	$ 204,766	$ 225,143

Deferred Tax Asset, Uncertain Income Tax

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from intangible assets including goodwill.

+ References

No definition available.

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory.

+ References

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

+ References

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-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from property, plant, and equipment.

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- Definition

Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards.

+ References

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from employee bonuses.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from reserves and accruals.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

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