CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
OPERATING ACTIVITIES:
Net Income	$ 118,228	$ 106,196
Items not affecting cash:
Depreciation and depletion	119,551	107,239
Amortization of debt issue costs, discount and deferred hedge gain	907	1,301
Stock-based compensation costs	4,474	3,275
Equity portion of allowance for funds used during construction	(3,053)	(6,568)
Gain on disposition of assets	(15)	(28)
Deferred income taxes	(4,720)	27,019
Changes in current assets and liabilities:
Restricted cash	(72)	(735)
Accounts receivable	37,589	46,025
Inventories	(853)	(3,598)
Other current assets	(2,107)	4,006
Accounts payable	(16,568)	(21,655)
Accrued expenses	60,852	19,307
Regulatory assets	6,847	8,985
Regulatory liabilities	(56,831)	12,739
Other noncurrent assets	(4,234)	(2,240)
Other noncurrent liabilities	(2,007)	3,209
Cash Provided by Operating Activities	257,988	304,477
INVESTING ACTIVITIES:
Property, plant, and equipment additions	(203,998)	(203,324)
Acquisitions	0	(143,328)
Proceeds from sale of assets	1,352	30,209
Change in restricted cash	0	11,758
Cash Used in Investing Activities	(202,646)	(304,685)
FINANCING ACTIVITIES:
Treasury stock activity	(727)	(829)
Dividends on common stock	(71,816)	(67,145)
Issuance of long-term debt	249,660	270,000
Repayments on long-term debt	(225,205)	(150,024)
Repayments of short-term borrowings, net	(7,563)	(49,897)
Financing costs	(6,608)	(12,124)
Cash Used in Financing Activities	(62,259)	(10,019)
Decrease in Cash and Cash Equivalents	(6,917)	(10,227)
Cash and Cash Equivalents, beginning of period	11,980	20,362
Cash and Cash Equivalents, end of period	5,063	10,135
Cash (received) paid during the period for:
Income taxes	(2,922)	27
Interest	56,118	52,106
Significant non-cash transactions:
Capital expenditures included in trade accounts payable	$ 11,803	$ 8,932