Statement of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
OPERATING REVENUES:
Natural gas transportation	$ 105,209	$ 112,258	$ 214,074	$ 229,591
Natural gas storage	3,085	2,825	6,130	5,977
Other	(15)	11	1	26
Total operating revenue	108,279	115,094	220,205	235,594
OPERATING EXPENSES:
General and administrative	11,804	13,421	24,537	27,502
Operation and maintenance	18,751	19,125	33,919	34,522
Depreciation	26,481	25,313	52,809	50,829
Regulatory Debits	908	1,213	1,847	2,461
Taxes, other than income taxes	4,446	4,206	9,107	8,987
Regulatory charge resulting from tax rate change	6,338	0	12,152	0
Other expense, net	44	0	359	0
Total operating expenses	68,772	63,278	134,730	124,301
OPERATING INCOME	39,507	51,816	85,475	111,293
OTHER (INCOME) AND OTHER EXPENSES:
Interest expense	7,442	8,448	15,506	16,811
Allowance for equity and borrowed funds used during construction (AFUDC)	(576)	(362)	(987)	(512)
Miscellaneous other (income) expenses, net	(181)	98	(661)	213
Total other (income) and other expenses	6,685	8,184	13,858	16,512
NET INCOME	32,822	43,632	71,617	94,781
Other comprehensive income (loss)	0	0	0	0
COMPREHENSIVE INCOME	$ 32,822	$ 43,632	$ 71,617	$ 94,781