Income Taxes (Tables)

12 Months Ended

Sep. 30, 2020

Income Tax Disclosure [Abstract]

Components of Income Tax Provision (Benefit)

	Year Ended September 30,
	2020		2019		2018
Current income tax provision (benefit):
Federal	$	1,122	$	963	$	—
State		1,137		510		917
Foreign		13,136		15,860		7,608
Total current income tax provision		15,395		17,333		8,525
Deferred income tax provision (benefit):
Federal		(2,045)		(8,633)		(48,815)
State		(695)		(2,138)		(5,518)
Foreign		(2,718)		(6,673)		(1,443)
Total deferred income tax provision (benefit)		(5,458)		(17,444)		(55,776)
Income tax provision (benefit)	$	9,937	$	(111)	$	(47,251)

Components of Income (Loss) Before Income Taxes and Equity in Earnings of Joint Ventures

	Year Ended September 30,
	2020		2019		2018
Domestic	$	20,697	$	(37,160)	$	3,122
Foreign		54,275		46,603		17,344
Income before income taxes	$	74,972	$	9,443	$	20,466

Differences between Income Tax Provision (benefit) and Income Taxes Computed using Applicable U.S. Statutory Federal Tax Rate

	Year Ended September 30,
	2020		2019		2018
Income tax provision computed at federal statutory rate	$	15,744	$	1,983	$	5,014
State income taxes, net of federal benefit		493		(630)		692
Foreign income taxed at different rates		132		550		920
Impact of investments in subsidiaries		296		(536)		(729)
Change in deferred tax asset valuation allowance		(1,526)		(2,264)		(75,918)
Net increase in uncertain tax positions		1,417		720		220
Global intangible low taxed income, net of foreign tax credits		611		1,389		—
Impact of tax rate changes		262		—		15,287
Compensation		(3,022)		(1,103)		(701)
Tax credits		(2,845)		(2,741)		(1,633)
Merger costs		37		572		1,405
Other taxes		580		764		70
Non-deductible expenses		116		174		176
Transition tax		—		2,988		8,027
Deferred state rate change due to acquisition		—		(1,360)		—
Prior year true ups		(1,645)		(152)
Research and development expense deduction		(530)		(447)		—
Foreign derived intangible income		(153)		—		—
Other		(30)		(18)		(81)
Income tax provision (benefit)	$	9,937	$	(111)	$	(47,251)

Significant Components of Net Deferred Tax Assets and Liabilities

	September 30,
	2020		2019
Accruals and reserves not currently deductible	$	17,245	$	14,286
Federal, state and foreign tax credits		5,625		5,952
Other assets		958		2,487
Equity compensation		4,141		5,360
Net operating loss carryforwards		15,556		18,987
Lease liabilities		9,534		—
Deferred revenue		3,494		4,038
Inventory reserves and valuation		6,522		5,626
Deferred tax assets		63,075		56,736
Depreciation and intangible amortization		(54,360)		(57,634)
Right-of-use assets		(9,524)		—
Deferred tax liabilities		(63,884)		(57,634)
Valuation allowance		(13,599)		(16,093)
Net deferred tax asset (liability)	$	(14,408)	$	(16,991)

Reconciliation of Beginning and Ending Amount of Consolidated Liability for Unrecognized Income Tax Benefits

	Total
Balance at September 30, 2017	$	3,378
Additions for tax positions in current year		874
Reduction for tax positions in prior year		(656)
Net reductions from lapses in statutes of limitations		(353)
Balance at September 30, 2018		3,243
Additions for tax positions in current year		901
Additions for tax positions in prior year		13,400
Reductions from lapses in statutes of limitations		(68)
Reductions from settlements with taxing authorities		(166)
Balance at September 30, 2019		17,310
Additions for tax positions in current year		448
Reductions from lapses in statutes of limitations		(64)
Reductions from settlements with taxing authorities		(522)
Balance at September 30, 2020	$	17,172