CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015		Dec. 31, 2014
Property, Plant and Equipment:
Utility Plant, at original cost	$ 2,042,333		$ 2,002,966
Accumulated Depreciation	(419,223)		(413,597)
Nonutility Property and Equipment, at cost	626,875		622,079
Accumulated Depreciation	(84,524)		(77,345)
Property, Plant and Equipment - Net	2,165,461		2,134,103
Investments:
Available-for-Sale Securities	15,245		8,922
Restricted	60,623		65,451
Investment in Affiliates	67,754		68,351
Total Investments	143,622		142,724
Current Assets:
Cash and Cash Equivalents	7,214		4,171
Accounts Receivable	322,803		251,892
Unbilled Revenues	63,547		62,608
Provision for Uncollectibles	(9,383)		(7,910)
Notes Receivable - Affiliate	15,921		14,657
Natural Gas in Storage, average cost	38,925		63,246
Materials and Supplies, average cost	2,112		2,125
Deferred Income Taxes - Net	56,696		57,748
Prepaid Taxes	4,429		14,106
Derivatives - Energy Related Assets	52,441		85,368
Other Prepayments and Current Assets	25,453		18,686
Total Current Assets	580,158		566,697
Regulatory and Other Noncurrent Assets:
Regulatory Assets	335,009		357,160
Derivatives - Energy Related Assets	15,402		13,905
Unamortized Debt Issuance Costs	9,449		9,795
Notes Receivable - Affiliate	36,525		36,799
Contract Receivables	21,607		19,236
Notes Receivable	7,882		7,882
Other	61,607		61,124
Total Regulatory and Other Noncurrent Assets	487,481		505,901
Total Assets	3,376,722		3,349,425
Equity:
Common Stock	85,530		85,418
Premium on Common Stock	440,882		438,384
Treasury Stock (at par)	(284)		(330)
Accumulated Other Comprehensive Loss	(30,257)	[1]	(30,258)	[1]
Retained Earnings	475,614		439,218
Total Equity	971,485		932,432
Long-Term Debt	859,491		859,491
Total Capitalization	1,830,976		1,791,923
Current Liabilities:
Notes Payable	272,400		245,700
Current Portion of Long-Term Debt	149,909		149,909
Accounts Payable	221,230		272,998
Customer Deposits and Credit Balances	16,052		17,958
Environmental Remediation Costs	38,186		30,430
Taxes Accrued	9,197		2,328
Derivatives - Energy Related Liabilities	81,779		109,744
Dividends Payable	17,191		0
Interest Accrued	6,578		7,088
Pension Benefits	1,515		1,550
Other Current Liabilities	7,584		12,480
Total Current Liabilities	821,621		850,185
Deferred Credits and Other Noncurrent Liabilities:
Deferred Income Taxes - Net	356,380		344,520
Investment Tax Credits	111		149
Pension and Other Postretirement Benefits	98,232		115,373
Environmental Remediation Costs	90,159		97,742
Asset Retirement Obligations	42,599		42,502
Derivatives - Energy Related Liabilities	24,522		19,926
Derivatives - Other	12,036		10,732
Regulatory Liabilities	66,526		41,899
Finance Obligation	19,420		19,659
Other	14,140		14,815
Total Deferred Credits and Other Noncurrent Liabilities	724,125		707,317
Commitments and Contingencies
Total Capitalization and Liabilities	$ 3,376,722		$ 3,349,425

[1] For 2015, determined using a combined average statutory tax rate of 40%. For 2014, determined using a combined statutory tax rate of 41%.