CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Operating activities
Net income	$ 46,605	$ 36,660
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	62,840	55,434
Deferred income taxes	2,426	22,588
Amortization of investment tax credits	(261)	(262)
Allowance for equity funds used during construction	(4,101)	(3,038)
Net derivative losses	166	115
Other, net	506	(1,505)
Changes in operating assets and liabilities:
Accounts receivable	2,571	(295)
Accrued unbilled revenues	14,811	10,846
Inventories	3,959	2,669
Other current assets	(129)	(58)
Accounts payable	(8,236)	28,882
Net regulatory assets and liabilities	14,584	(3,112)
Other current liabilities	(331)	(9,191)
Pension and other employee benefit obligations	(8,969)	(8,735)
Change in other noncurrent assets	179	(359)
Change in other noncurrent liabilities	365	(2,696)
Net cash provided by operating activities	126,985	127,943
Investing activities
Utility capital/construction expenditures	(121,198)	(90,735)
Allowance for equity funds used during construction	4,101	3,038
Other, net	(104)	(33)
Net cash used in investing activities	(117,201)	(87,730)
Financing activities
Proceeds from (repayments of) short-term borrowings, net	19,000	(14,000)
Repayments of long-term debt	(10)	(27)
Capital contributions from parent	3,326	12,282
Dividends paid to parent	(31,522)	(38,800)
Other, net	(413)	(70)
Net cash used in financing activities	(9,619)	(40,615)
Net change in cash and cash equivalents	165	(402)
Cash and cash equivalents at beginning of period	1,403	1,546
Cash and cash equivalents at end of period	1,568	1,144
Supplemental disclosure of cash flow information:
Cash paid for interest (net of amounts capitalized)	(16,494)	(15,062)
Cash paid for income taxes, net	(12,495)	(9,699)
Supplemental disclosure of non-cash investing transactions:
Property, plant and equipment additions in accounts payable	$ 18,785	$ 21,867