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Commitments and Contingencies (Details Textual) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2021	Jun. 30, 2023	Jun. 30, 2022
Loss Contingencies [Line Items]
Unpriced Change Orders and Claims		$ 9.7	$ 8.9
Loss Contingency, Receivable, Period Increase (Decrease)	$ (2.9)
Loss Contingency, Receivable, Proceeds	$ 8.9
Case 1 [Member]
Loss Contingencies [Line Items]
Contract receivable in dispute		5.6
Case 2 [Member]
Loss Contingencies [Line Items]
Contract receivable in dispute		32.7
Case 3 [Member]
Loss Contingencies [Line Items]
Contract receivable in dispute		$ 17.0