Short-Term Debt - Additional Information (Details) - USD ($) $ in Thousands	Mar. 30, 2021	Jun. 30, 2021
Short Term Debt [Line Items]
Short-term debt		$ 11,884
Glatfelter Gernsbach GmbH [Member]
Short Term Debt [Line Items]
Short-term debt	$ 11,700
Short-term debt, Lender	Commerzbank AG
Fixed interest rate of borrowings	0.75%
Maturity date of loan	Mar. 29, 2022

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a))
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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Name:	us-gaap_ShortTermBorrowings
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant