BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment:
Utility Plant, at original cost	$ 2,424,134	$ 2,211,239
Accumulated Depreciation	(471,222)	(440,473)
Property, Plant and Equipment - Net	1,952,912	1,770,766
Investments:
Available-for-Sale Securities	0	8,788
Restricted Investments	32	6,769
Total Investments	32	15,557
Current Assets:
Cash and Cash Equivalents	1,359	775
Notes Receivable	0	9,916
Accounts Receivable	69,651	64,445
Accounts Receivable - Related Parties	1,355	1,972
Unbilled Revenues	41,754	25,613
Provision for Uncollectibles	(12,570)	(9,778)
Natural Gas in Storage, average cost	11,621	14,294
Materials and Supplies, average cost	914	937
Prepaid Taxes	16,428	21,483
Derivatives - Energy Related Assets	5,434	1,077
Other Prepayments and Current Assets	13,853	13,405
Total Current Assets	149,799	144,139
Regulatory and Other Noncurrent Assets:
Regulatory Assets	410,746	323,434
Long-Term Receivables	25,758	24,950
Derivatives - Energy Related Assets	373	64
Other	12,303	2,666
Total Regulatory and Other Noncurrent Assets	449,180	351,114
Total Assets	2,551,923	2,281,576
Common Equity:
Common Stock, Par Value $2.50 per share: Authorized - 4,000,000 shares, Outstanding - 2,339,139 shares	5,848	5,848
Other Paid-In Capital and Premium on Common Stock	315,827	250,827
Accumulated Other Comprehensive Loss	(14,934)	(12,862)
Retained Earnings	533,159	464,114
Total Common Equity	839,900	707,927
Long-Term Debt (See Note 1)	423,177	577,454
Total Capitalization	1,263,077	1,285,381
Current Liabilities:
Notes Payable	104,300	134,400
Current Portion of Long-Term Debt	215,909	27,909
Accounts Payable - Commodity	23,815	8,936
Accounts Payable - Other	45,370	40,579
Accounts Payable - Related Parties	11,216	7,552
Derivatives - Energy Related Liabilities	1,372	5,489
Derivatives - Other Current	386	0
Customer Deposits and Credit Balances	45,816	19,531
Environmental Remediation Costs	45,018	48,323
Taxes Accrued	855	1,930
Pension Benefits	2,428	2,227
Interest Accrued	5,369	5,989
Other Current Liabilities	8,011	5,686
Total Current Liabilities	509,865	308,551
Regulatory and Other Noncurrent Liabilities:
Regulatory Liabilities	49,121	42,841
Deferred Income Taxes - Net	469,408	432,674
Environmental Remediation Costs	108,029	74,871
Asset Retirement Obligations	58,674	57,219
Pension and Other Postretirement Benefits	81,800	65,491
Derivatives - Energy Related Liabilities	0	351
Derivatives - Other	6,979	7,631
Other	4,970	6,566
Total Regulatory and Other Noncurrent Liabilities	778,981	687,644
Commitments and Contingencies (Note 12)
Total Capitalization and Liabilities	$ 2,551,923	$ 2,281,576