Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands		1 Months Ended					12 Months Ended
	Nov. 28, 2018	Jul. 31, 2018	Dec. 31, 2017	Nov. 30, 2017	Aug. 31, 2017	Oct. 31, 2016	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016	Oct. 01, 2018	Jul. 26, 2018	Dec. 20, 2017	Oct. 28, 2016
Finite-Lived Intangible Assets [Line Items]
Debt instrument, fee amount		$ 1,346
Amortization of debt issuance costs and discounts							$ 1,991	$ 2,498	$ 4,607
Write off of deferred debt issuance cost		$ 2,581	$ 1,150	$ 1,844	$ 1,829	$ 2,075	0	5,575		$ 3,094
Prepayment of debt				$ 100,000
Foreign currency losses (gains) on intracompany loans							12,599	7,018	(7,111)
Research and development costs							$ 15,300	15,877	$ 19,990
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life							1 year
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life							26 years
Machinery and equipment | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Property, plant and equipment, useful life							3 years
Machinery and equipment | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Property, plant and equipment, useful life							20 years
Building and Building Improvements | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Property, plant and equipment, useful life							10 years
Building and Building Improvements | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Property, plant and equipment, useful life							40 years
Tack-On Financing Completed October 28, 2016 [Member]
Finite-Lived Intangible Assets [Line Items]
Debt instrument, fee amount														$ 481
December Refinancing [Member]
Finite-Lived Intangible Assets [Line Items]
Debt instrument, fee amount								2,131
First Lien Term Loan, due December 20, 2024
Finite-Lived Intangible Assets [Line Items]
Debt instrument, fee amount					$ 1,188
Term Loan [Member] | First Lien Term Loan, due December 20, 2024
Finite-Lived Intangible Assets [Line Items]
Line of credit facility, remaining borrowing capacity												$ 150,000
Revolving Credit Facility
Finite-Lived Intangible Assets [Line Items]
Line of credit facility, remaining borrowing capacity							$ 125,000	$ 125,000					$ 125,000
Interest Rate Cap [Member]
Finite-Lived Intangible Assets [Line Items]
Derivative, Cost of Hedge Net of Cash Received	$ 2,235
Derivative, Term of Contract	3 years
Amortization							621
Accounting Standards Update 2014-09 [Member]
Finite-Lived Intangible Assets [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets											$ (1,582)
Accounting Standards Update 2016-02 [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets							38,000
Accounting Standards Update 2016-02 [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets							$ 42,000