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

3 Months Ended

Mar. 31, 2021

Credit Loss [Abstract]

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

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

	Electric		Natural gas distribution		Pipeline		Construction materials and contracting		Construction services		Total
	(In thousands)
At December 31, 2020	$	899	$	2,571	$	2	$	6,164	$	5,722	$	15,358
Current expected credit loss provision	538		1,273		—		(1,049)		(1,079)		(317)
Less write-offs charged against the allowance	888		1,107		—		273		401		2,669
Credit loss recoveries collected	129		213		—		—		—		342
At March 31, 2021	$	678	$	2,950	$	2	$	4,842	$	4,242	$	12,714

	Electric		Natural gas distribution		Pipeline		Construction materials and contracting		Construction services		Total
	(In thousands)
At January 1, 2020	$	328	$	1,056	$	—	$	5,357	$	1,756	$	8,497
Current expected credit loss provision	555		1,156		—		694		1,150		3,555
Less write-offs charged against the allowance	500		624		—		68		73		1,265
Credit loss recoveries collected	109		229		—		—		—		338
At March 31, 2020	$	492	$	1,817	$	—	$	5,983	$	2,833	$	11,125