Operating Segments (Tables)

3 Months Ended

Dec. 31, 2020

Segment Reporting [Abstract]

Schedule of Segment Reporting Information, by Segment [Table Text Block]

		Three Months Ended December 31, 2020
		Communications		Residential		Infrastructure Solutions		Commercial & Industrial		Corporate		Total
Revenues		$	98,356	$	119,491	$	34,401	$	62,590	$	—	$	314,838
Cost of services		79,817		95,963		23,464		56,915		—		256,159
Gross profit		18,539		23,528		10,937		5,675		—		58,679
Selling, general and administrative		9,341		17,327		5,611		6,424		4,083		42,786
Gain on sale of assets		—		—		(1)		(9)		—		(10)
Operating income (loss)		9,198		6,201		5,327		(740)		(4,083)		15,903
Other data:
	Depreciation and amortization expense	$	347	$	1,504	$	1,441	$	694	$	34	$	4,020
	Capital expenditures	$	132	$	437	$	345	$	268	$	—	$	1,182
	Total assets	$	137,457	$	198,227	$	129,283	$	72,148	$	72,255	$	609,370

		Three Months Ended December 31, 2019
		Communications		Residential		Infrastructure Solutions		Commercial & Industrial		Corporate		Total
Revenues		$	84,289	$	92,728	$	31,283	$	67,743	$	—	$	276,043
Cost of services		68,722		72,585		23,513		61,008		—		225,828
Gross profit		15,567		20,143		7,770		6,735		—		50,215
Selling, general and administrative		8,569		13,720		4,493		7,288		3,802		37,872
Gain on sale of assets		(9)		—		—		(27)		—		(36)
Operating income (loss)		7,007		6,423		3,277		(526)		(3,802)		12,379
Other data:
	Depreciation and amortization expense	$	337	$	210	$	1,120	$	676	$	19	$	2,362
	Capital expenditures	$	282	$	212	$	437	$	460	$	—	$	1,391
	Total assets	$	113,574	$	77,109	$	112,413	$	80,612	$	86,157	$	469,865