Balance Sheet (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
CURRENT ASSETS:
Cash	$ 0	$ 0
Receivables:
Trade	39,272	38,884
Affiliated companies	2,048	1,921
Advances to affiliate	167,486	137,666
Other	1,195	2,618
Materials and supplies	10,101	10,084
Exchange gas due from others	2,512	2,720
Prepayments and other	4,882	6,423
Total current assets	227,496	200,316
PROPERTY, PLANT AND EQUIPMENT, at cost	3,404,327	3,396,776
Less-Accumulated depreciation and amortization	1,531,439	1,508,245
Total property, plant and equipment, net	1,872,888	1,888,531
OTHER ASSETS:
Deferred charges	832	934
Regulatory assets	22,604	22,747
Total other assets	23,436	23,681
Total assets	2,123,820	2,112,528
Payables:
Trade	7,583	11,053
Affiliated companies	5,665	11,298
Accrued liabilities:
Taxes, other than income taxes	15,199	11,617
Interest	11,472	3,677
Exchange gas due to others	2,793	4,500
Exchange gas offset	1,370	1,499
Customer advances	2,552	2,092
Other	3,379	6,655
Long-term debt due within one year	249,943	249,874
Total current liabilities	299,956	302,265
LONG-TERM DEBT	331,708	331,748
OTHER NONCURRENT LIABILITIES:
Asset retirement obligations	68,223	67,100
Regulatory liabilities	254,273	246,504
Other	1,684	1,730
Total other noncurrent liabilities	324,180	315,334
CONTINGENT LIABILITIES AND COMMITMENTS (Note 4)
MEMBER'S EQUITY:
Member's capital	1,073,892	1,073,892
Retained earnings	94,084	89,289
Total member's equity	1,167,976	1,163,181
Total liabilities and member's equity	$ 2,123,820	$ 2,112,528