Consolidated Statement of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Operating activities:
Net income	$ 40,607	$ 40,773
Adjustments to reconcile net income to cash provided by operations:
Depreciation and amortization	17,950	17,309
Deferred tax liabilities	27,089	25,048
Undistributed earnings from equity investments	1	25
Non-cash expenses related to qualified defined benefit pension plans	2,007	1,817
Contributions to qualified defined benefit pension plans	(13,800)	(13,645)
Deferred environmental expenditures	(827)	(1,759)
Other	475	(443)
Changes in assets and liabilities:
Receivables	6,378	(3,122)
Inventories	12,927	27,119
Taxes accrued	5,072	16,905
Accounts payable	(26,050)	(14,406)
Interest accrued	4,791	6,288
Deferred gas costs	23,663	196
Other - net	13,771	5,959
Cash provided by operating activities	114,054	108,064
Investing activities:
Capital expenditures	(20,447)	(25,403)
Utility gas reserves	(17,220)	0
Restricted cash	0	0
Other	(68)	(121)
Cash used in investing activities	(37,735)	(25,524)
Financing activities:
Common stock issued (purchased) - net, including common stock expense	1,458	(244)
Long-term debt issued	0	0
Long-term debt retired	(40,000)	0
Change in short-term debt	(27,900)	(71,000)
Cash dividend payments on common stock	(11,913)	(11,601)
Other	234	328
Cash used in financing activities	(78,121)	(82,517)
Increase (decrease) in cash and cash equivalents	(1,802)	23
Cash and cash equivalents - beginning of period	5,833	3,457
Cash and cash equivalents - end of period	4,031	3,480
Supplemental disclosure of cash flow information:
Interest paid	6,148	4,162
Income taxes paid	$ 101	$ 0