Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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SCHEDULE I - Evoqua Water Technologies Corp. (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jan. 31, 2020	Sep. 30, 2019
Debt Instrument [Line Items]
Long-term debt, gross	$ 885,470		$ 977,155
First Lien Term Loan, due December 20, 2024
Debt Instrument [Line Items]
Long-term debt, gross	819,276	$ 826,000	$ 928,753
Parent Company [Member] \| First Lien Term Loan, due December 20, 2024
Debt Instrument [Line Items]
Long-term debt, gross	$ 819,276