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Amount, before allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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No definition available.

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Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended
Revenue Recognition (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Sep. 30, 2022
Revenue Recognition and Deferred Revenue [Abstract]
Unbilled Receivables, Current	$ 15,135
Costs and estimated earnings in excess of billings	44,515		$ 52,076
Billings in excess of costs and estimated earnings	(95,442)		$ (84,936)
Contract with Customer, Liability, Revenue Recognized	38,047	$ 28,341
Performance Obligation Next 12 Months	921,848
Revenue, Remaining Performance Obligation, Amount	1,011,018
Disaggregation of Revenue [Line Items]
Revenues	574,874	480,509
Contract with Customer, Liability, Revenue Recognized	38,047	28,341
Commercial and Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenues	60,267	69,248
Communications [Member]
Disaggregation of Revenue [Line Items]
Revenues	147,245	127,389
Infrastructure Solutions [Member]
Disaggregation of Revenue [Line Items]
Revenues	49,284	42,096
Residential [Member]
Disaggregation of Revenue [Line Items]
Revenues	318,078	241,776
Fixed-price Contract [Member]
Disaggregation of Revenue [Line Items]
Revenues	507,495	435,511
Fixed-price Contract [Member] \| Commercial and Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenues	54,597	64,860
Fixed-price Contract [Member] \| Communications [Member]
Disaggregation of Revenue [Line Items]
Revenues	87,274	88,422
Fixed-price Contract [Member] \| Infrastructure Solutions [Member]
Disaggregation of Revenue [Line Items]
Revenues	47,546	40,453
Fixed-price Contract [Member] \| Residential [Member]
Disaggregation of Revenue [Line Items]
Revenues	318,078	241,776
Time-and-materials Contract [Member]
Disaggregation of Revenue [Line Items]
Revenues	67,379	44,998
Time-and-materials Contract [Member] \| Commercial and Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenues	5,670	4,388
Time-and-materials Contract [Member] \| Communications [Member]
Disaggregation of Revenue [Line Items]
Revenues	59,971	38,967
Time-and-materials Contract [Member] \| Infrastructure Solutions [Member]
Disaggregation of Revenue [Line Items]
Revenues	1,738	1,643
Time-and-materials Contract [Member] \| Residential [Member]
Disaggregation of Revenue [Line Items]
Revenues	0	0
industrial Services [Member] \| Infrastructure Solutions [Member]
Disaggregation of Revenue [Line Items]
Revenues	20,099	14,816
Custom Power Solutions [Member] \| Infrastructure Solutions [Member]
Disaggregation of Revenue [Line Items]
Revenues	29,185	27,280
Single Family Contracts [Member] \| Residential [Member]
Disaggregation of Revenue [Line Items]
Revenues	226,828	173,528
Multi Family and Other [Member] \| Residential [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 91,250	$ 68,248