Acquisitions and Dispositions - Preliminary Valuation of Identifiable Intangible Assets and Amortization Periods (Details) - USD ($) $ in Millions		9 Months Ended
Jun. 28, 2019	Mar. 31, 2020
Harsco Clean Earth Segment
Acquired Finite-Lived Intangible Assets [Line Items]
Preliminary Valuation	$ 261.1	$ 242.2
Harsco Clean Earth Segment \| Permits
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted-Average Amortization Period	18 years
Preliminary Valuation	$ 176.1	170.1
Harsco Clean Earth Segment \| Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted-Average Amortization Period	8 years
Preliminary Valuation	$ 33.4	20.5
Harsco Clean Earth Segment \| Air rights
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted-Average Amortization Period	27 years
Preliminary Valuation	$ 25.6	25.6
Harsco Clean Earth Segment \| Trade names
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted-Average Amortization Period	12 years
Preliminary Valuation	$ 26.0	26.0
Harsco Clean Earth Segment
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets		(18.9)
Customer Relationships		(12.9)
Permits		(6.0)
Harsco Clean Earth Segment \| Harsco Clean Earth Segment
Acquired Finite-Lived Intangible Assets [Line Items]
Preliminary Valuation	$ 261.1
Intangible assets		$ (18.9)

Business Combination Provisional Information Initial Accounting Incomplete Adjustment Customer Relationships

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Business Combination Provisional Information Initial Accounting Incomplete Adjustment Permits

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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