Segment Information (Tables)

3 Months Ended

Mar. 31, 2020

Segment Reporting [Abstract]

Accounts Receivable for Services

Accounts receivable for these services, which are not eliminated during consolidation, are presented in the table below:

(Thousands of dollars)	March 31, 2020		December 31, 2019
Centuri accounts receivable for services provided to Southwest	$	16,263	$	15,235

Schedule of Segment Reporting Information

The financial information pertaining to the natural gas operations and utility infrastructure services segments is as follows:

(Thousands of dollars)	Natural Gas Operations		Utility Infrastructure Services			Other			Total
Three Months Ended March 31, 2020
Revenues from external customers	$	502,827	$	300,291		$	—		$	803,118
Intersegment revenues	—		33,202			—			33,202
Total	$	502,827	$	333,493		$	—		$	836,320
Segment net income (loss)	$	83,599	$	(10,204	)	$	(853	)	$	72,542
Three Months Ended March 31, 2019
Revenues from external customers	$	520,677	$	274,189		$	—		$	794,866
Intersegment revenues	—		38,673			—			38,673
Total	$	520,677	$	312,862		$	—		$	833,539
Segment net income (loss)	$	103,389	$	(8,031	)	$	(549	)	$	94,809

(Thousands of dollars)	Natural Gas Operations		Utility Infrastructure Services		Other			Total
Twelve Months Ended March 31, 2020
Revenues from external customers	$	1,351,089	$	1,618,354	$	—		$	2,969,443
Intersegment revenues	—		153,255		—			153,255
Total	$	1,351,089	$	1,771,609	$	—		$	3,122,698
Segment net income (loss)	$	143,381	$	50,231	$	(1,943	)	$	191,669
Twelve Months Ended March 31, 2019
Revenues from external customers	$	1,384,092	$	1,427,701	$	—		$	2,811,793
Intersegment revenues	—		147,429		—			147,429
Total	$	1,384,092	$	1,575,130	$	—		$	2,959,222
Segment net income (loss)	$	151,882	$	47,947	$	(1,834	)	$	197,995