STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Gross Margin
Revenues	$ 232,191	$ 225,226	$ 986,479	$ 1,158,543
Cost of natural gas	52,253	54,724	344,439	548,226
Net margin	179,938	170,502	642,040	610,317
Operating expenses
Operations and maintenance	99,402	98,698	302,652	304,681
Depreciation and amortization	36,241	33,956	106,490	98,592
General taxes	13,403	12,897	42,311	41,818
Total operating expenses	149,046	145,551	451,453	445,091
Operating income	30,892	24,951	190,587	165,226
Other income	911	166	1,345	1,051
Other expense	(357)	(1,884)	(1,126)	(2,840)
Interest expense, net	(10,809)	(11,233)	(32,504)	(33,592)
Income before income taxes	20,637	12,000	158,302	129,845
Income taxes	(7,900)	(4,629)	(60,521)	(50,017)
Net income	$ 12,737	$ 7,371	$ 97,781	$ 79,828
Earnings per share
Basic	$ 0.24	$ 0.14	$ 1.86	$ 1.52
Diluted	$ 0.24	$ 0.14	$ 1.85	$ 1.50
Average shares (thousands)
Basic	52,453	52,408	52,452	52,627
Diluted	52,942	53,072	52,962	53,315
Dividends declared per share of stock	$ 0.35	$ 0.30	$ 1.05	$ 0.90