Accounts receivable and allowance for doubtful accounts Receivables and allowance for expected credit losses (Tables)

3 Months Ended

Mar. 31, 2020

Credit Loss [Abstract]

Financing Receivable, Allowance for Credit Loss [Table Text Block]

Details of the Company's expected credit losses were as follows:

	Balance at January 1, 2020		Current Expected Credit Loss Provision		Write-offs Charged Against the Allowance		Credit Loss Recoveries Collected		Balance at March 31, 2020
	(In thousands)
Electric	$	328	$	555	$	500	$	109	$	492
Natural gas distribution	1,056		1,156		624		229		1,817
Construction materials and contracting	5,357		694		68		—		5,983
Construction services	1,756		1,150		73		—		2,833
Total	$	8,497	$	3,555	$	1,265	$	338	$	11,125