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- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

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- Definition

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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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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- Definition

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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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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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No definition available.

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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.

+ References

No definition available.

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Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Revenue Recognition (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020	Sep. 30, 2020
Revenue Recognition and Deferred Revenue [Abstract]
Capitalized Contract Cost, Net	$ 94		$ 94
Unbilled Receivables, Current	12,302		12,302
Costs and estimated earnings in excess of billings	24,239		24,239		$ 29,937
Billings in excess of costs and estimated earnings	(60,257)		(60,257)		$ (55,739)
Contract with Customer, Liability, Revenue Recognized	28,385	$ 21,473	33,740	$ 26,403
Performance Obligation Next 12 Months	458,306		458,306
Revenue, Remaining Performance Obligation, Amount	613,893		613,893
Disaggregation of Revenue [Line Items]
Revenues	331,961	291,277	646,799	567,320
Contract with Customer, Liability, Revenue Recognized	28,385	21,473	33,740	26,403
Commercial and Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenues	52,023	65,960	114,613	133,703
Communications [Member]
Disaggregation of Revenue [Line Items]
Revenues	94,886	95,990	193,242	180,279
Infrastructure Solutions [Member]
Disaggregation of Revenue [Line Items]
Revenues	34,716	29,300	69,117	60,583
Residential [Member]
Disaggregation of Revenue [Line Items]
Revenues	150,336	100,027	269,827	192,755
Fixed-price Contract [Member]
Disaggregation of Revenue [Line Items]
Revenues	300,849	263,459	589,705	511,540
Fixed-price Contract [Member] \| Commercial and Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenues	49,003	62,779	109,690	126,614
Fixed-price Contract [Member] \| Communications [Member]
Disaggregation of Revenue [Line Items]
Revenues	68,551	71,377	144,565	133,404
Fixed-price Contract [Member] \| Infrastructure Solutions [Member]
Disaggregation of Revenue [Line Items]
Revenues	32,959	29,276	65,623	58,767
Fixed-price Contract [Member] \| Residential [Member]
Disaggregation of Revenue [Line Items]
Revenues	150,336	100,027	269,827	192,755
Time-and-materials Contract [Member]
Disaggregation of Revenue [Line Items]
Revenues	31,112	27,818	57,094	55,780
Time-and-materials Contract [Member] \| Commercial and Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenues	3,020	3,181	4,923	7,089
Time-and-materials Contract [Member] \| Communications [Member]
Disaggregation of Revenue [Line Items]
Revenues	26,335	24,613	48,677	46,875
Time-and-materials Contract [Member] \| Infrastructure Solutions [Member]
Disaggregation of Revenue [Line Items]
Revenues	1,757	24	3,494	1,816
Time-and-materials Contract [Member] \| Residential [Member]
Disaggregation of Revenue [Line Items]
Revenues	0	0	0	0
industrial Services [Member] \| Infrastructure Solutions [Member]
Disaggregation of Revenue [Line Items]
Revenues	10,548	10,724	20,588	21,835
Custom Power Solutions [Member] \| Infrastructure Solutions [Member]
Disaggregation of Revenue [Line Items]
Revenues	24,168	18,576	48,529	38,748
Single Family Contracts [Member] \| Residential [Member]
Disaggregation of Revenue [Line Items]
Revenues	100,476	58,958	172,602	113,832
Multi Family and Other [Member] \| Residential [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 49,860	$ 41,069	$ 97,225	$ 78,923