The estimated cost of the remedy selected by EPA.

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The estimated amount of time to complete the selected EPA remedy.

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Number of potentially responsible parties for Portland Harbor Superfund site.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

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Cash received for the settlement of litigation during the current period.

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Note 8 - Commitments and Contingencies (Details Textual) $ in Millions	1 Months Ended	3 Months Ended
	Jan. 31, 2017 USD ($)	Jun. 30, 2026 USD ($)	Nov. 30, 2024	Jun. 30, 2014 USD ($)
Letters of Credit Outstanding, Amount		$ 1.1
Capital Addition Purchase Commitments [Member] \| Catch Basin Machine [Member]
Other Commitment		1.3
Capital Addition Purchase Commitments [Member] \| Pipe Profiler Equipment [Member]
Other Commitment		0.8
Portland Harbor Natural Resources Trustee Council [Member]
Loss Contingency, Accrual, Current				$ 0.4
Proceeds from Legal Settlements		$ 0.1
Portland Harbor Superfund Site [Member]
Number Of Potentially Responsible Parties			60
Estimated Cost of EPA Selected Remedy	$ 1,000.0
Estimated Time to Complete Selected EPA Remedy (Year)	13 years
Lower Willamette Group [Member]
Number Of Potentially Responsible Parties	14