Consolidated Statement of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Operating activities:
Net income	$ 28,745	$ 34,544
Adjustments to reconcile net income to cash provided by operations:
Depreciation and amortization	63,507	60,529
Regulatory amortization of gas reserves	12,056	12,036
Deferred income taxes	3,954	17,287
Qualified defined benefit pension plan expense	4,450	3,923
Contributions to qualified defined benefit pension plans	(11,690)	(15,400)
Deferred environmental expenditures, net	(10,547)	(10,468)
Amortization of environmental remediation	7,528	10,920
Regulatory revenue deferral from the TCJA	6,983	0
Other	1,541	2,522
Changes in assets and liabilities:
Receivables, net	83,194	90,311
Inventories	(5,134)	(5,372)
Income taxes	(5,809)	(216)
Accounts payable	(22,929)	(29,282)
Interest accrued	2,680	3,888
Deferred gas costs	2,372	13,419
Other, net	(3,588)	28
Discontinued operations	1,216	4,187
Cash provided by operating activities	158,529	192,856
Investing activities:
Capital expenditures	(158,795)	(145,274)
Other	(1,661)	(1,131)
Discontinued operations	(619)	(167)
Cash used in investing activities	(161,075)	(146,572)
Financing activities:
Repurchases related to stock-based compensation	0	(2,034)
Proceeds from stock options exercised	1,368	3,711
Long-term debt issued	50,000	100,000
Long-term debt retired	(22,000)	(40,000)
Change in short-term debt	46,300	(53,300)
Cash dividend payments on common stock	(38,387)	(40,390)
Stock purchases related to acquisitions	(7,951)	0
Other	(291)	(2,012)
Cash provided by (used in) financing activities	29,039	(34,025)
Increase in cash and cash equivalents	26,493	12,259
Cash and cash equivalents, beginning of period	3,472	3,521
Cash and cash equivalents, end of period	29,965	15,780
Supplemental disclosure of cash flow information:
Interest paid, net of capitalization	22,821	22,859
Income taxes paid, net of refunds	$ 22,047	$ 11,581