Commitments and Contingencies (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Sep. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Accrued Insurance, Current	$ 6,238	$ 6,683
Liability for Claims and Claims Adjustment Expense	34	90
Loss Contingencies [Line Items]
Letters of Credit Outstanding, Amount	6,962
Estimated cost of completion of bonded projects	101,229
Insurance Related [Member]
Loss Contingencies [Line Items]
Letters of Credit Outstanding, Amount	$ 6,762	6,268
Vendor Related [Member]
Loss Contingencies [Line Items]
Letters of Credit Outstanding, Amount		$ 200