Accounts Receivable:

3 Months Ended

Mar. 31, 2019

Receivables [Abstract]

Accounts Receivable

ACCOUNTS RECEIVABLE

Following is a summary of Accounts receivable, net included in the accompanying Condensed Consolidated Balance Sheets (in thousands) as of:

	Accounts		Unbilled		Less Allowance for			Accounts
March 31, 2019	Receivable, Trade		Revenue		Doubtful Accounts			Receivable, net
Electric Utilities	$	45,764	$	31,075	$	(535	)	$	76,304
Gas Utilities	138,005		62,566		(4,008		)	196,563
Power Generation	3,167		—		—			3,167
Mining	2,791		—		—			2,791
Corporate	3,946		—		(169		)	3,777
Total	$	193,673	$	93,641	$	(4,712	)	$	282,602

	Accounts		Unbilled		Less Allowance for			Accounts
December 31, 2018	Receivable, Trade		Revenue		Doubtful Accounts			Receivable, net
Electric Utilities	$	39,721	$	35,125	$	(448	)	$	74,398
Gas Utilities	96,123		90,521		(2,592		)	184,052
Power Generation	1,876		—		—			1,876
Mining	3,988		—		—			3,988
Corporate	5,008		—		(169		)	4,839
Total	$	146,716	$	125,646	$	(3,209	)	$	269,153

	Accounts		Unbilled		Less Allowance for			Accounts
March 31, 2018	Receivable, Trade		Revenue		Doubtful Accounts			Receivable, net
Electric Utilities	$	40,492	$	33,907	$	(624	)	$	73,775
Gas Utilities	120,910		60,142		(3,684		)	177,368
Power Generation	1,580		—		—			1,580
Mining	3,133		—		—			3,133
Corporate	1,916		—		—			1,916
Total	$	168,031	$	94,049	$	(4,308	)	$	257,772