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

9 Months Ended

Sep. 30, 2020

Credit Loss [Abstract]

Financing 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 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
Current expected credit loss provision	303		190		—		(314)		896		1,075
Less write-offs charged against the allowance	224		677		—		44		454		1,399
Credit loss recoveries collected	88		201		—		—		—		289
At June 30, 2020	$	659	$	1,531	$	—	$	5,625	$	3,275	$	11,090
Current expected credit loss provision	435		811		2		728		1,635		3,611
Less write-offs charged against the allowance	269		692		—		229		117		1,307
Credit loss recoveries collected	75		203		—		—		—		278
At September 30, 2020	$	900	$	1,853	$	2	$	6,124	$	4,793	$	13,672