Segment Information (Tables)

6 Months Ended

Jun. 30, 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)	June 30, 2020		December 31, 2019
Centuri accounts receivable for services provided to Southwest	$	17,364	$	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 June 30, 2020
Revenues from external customers	$	262,434	$	457,890	$	—	$	720,324
Intersegment revenues	—		36,923		—		36,923
Total	$	262,434	$	494,813	$	—	$	757,247
Segment net income (loss)	$	11,942	$	26,267	$	(244)	$	37,965
Three Months Ended June 30, 2019
Revenues from external customers	$	258,711	$	405,218	$	—	$	663,929
Intersegment revenues	—		49,082		—		49,082
Total	$	258,711	$	454,300	$	—	$	713,011
Segment net income (loss)	$	3,369	$	18,918	$	(231)	$	22,056
(Thousands of dollars)	Natural Gas Operations		Utility Infrastructure Services		Other		Total
Six Months Ended June 30, 2020
Revenues from external customers	$	765,261	$	758,181	$	—	$	1,523,442
Intersegment revenues	—		70,125		—		70,125
Total	$	765,261	$	828,306	$	—	$	1,593,567
Segment net income (loss)	$	95,541	$	16,063	$	(1,097)	$	110,507
Six Months Ended June 30, 2019
Revenues from external customers	$	779,388	$	679,407	$	—	$	1,458,795
Intersegment revenues	—		87,755		—		87,755
Total	$	779,388	$	767,162	$	—	$	1,546,550
Segment net income (loss)	$	106,758	$	10,887	$	(780)	$	116,865

(Thousands of dollars)	Natural Gas Operations		Utility Infrastructure Services		Other		Total
Twelve Months Ended June 30, 2020
Revenues from external customers	$	1,354,812	$	1,671,026	$	—	$	3,025,838
Intersegment revenues	—		141,096		—		141,096
Total	$	1,354,812	$	1,812,122	$	—	$	3,166,934
Segment net income (loss)	$	151,954	$	57,581	$	(1,957)	$	207,578
Twelve Months Ended June 30, 2019
Revenues from external customers	$	1,367,124	$	1,470,787	$	—	$	2,837,911
Intersegment revenues	—		163,439		—		163,439
Total	$	1,367,124	$	1,634,226	$	—	$	3,001,350
Segment net income (loss)	$	152,629	$	47,629	$	(1,758)	$	198,500