Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Operating Activities
Net Income	$ 28,863	$ 27,622	$ 26,056
Adjustments to reconcile net income to net operating cash:
Depreciation and amortization	22,510	20,153	18,536
Depreciation and accretion included in other costs	5,547	5,116	4,365
Deferred income taxes, net	13,881	17,320	13,332
(Gain) loss on sale of assets	93	(453)	113
Unrealized (gain) loss on commodity contracts	339	(41)	(116)
Unrealized gain on investments	(451)	(282)	(181)
Realized gain on sale of investments, net	(88)
Employee benefits and compensation	576	1,457	1,801
Share based compensation	1,419	1,450	1,155
Other, net	(27)	(50)	(17)
Changes in assets and liabilities:
Sale (purchase) of investments	(301)	660	(297)
Accounts receivable and accrued revenue	21,549	14,979	(20,467)
Propane inventory, storage gas and other inventory	603	(2,484)	151
Regulatory assets	252	(18)	1,659
Prepaid expenses and other current assets	(713)	(345)	1,157
Other deferred charges	26	179	(156)
Long-term receivables	(290)	76	286
Accounts payable and other accrued liabilities	(19,936)	(13,612)	15,853
Income taxes receivable	2,223	(185)	(3,761)
Accrued interest	(200)	(152)	(97)
Customer deposits and refunds	(1,647)	5,096	2,038
Accrued compensation	437	19	1,339
Regulatory liabilities	(5,220)	(2,527)	740
Other liabilities	(3,573)	(2,893)	(2,371)
Net cash provided by operating activities	65,872	71,121	61,118
Investing Activities
Property, plant and equipment expenditures	(72,007)	(47,037)	(45,637)
Proceeds from sale of assets	2,279	937	113
Sale (Purchase) of investments	506	(1,091)	(3,108)
Environmental expenditures	(607)	(645)	(290)
Net cash used by investing activities	(69,829)	(47,836)	(48,922)
Financing Activities
Common stock dividends	(12,335)	(11,663)	(11,013)
(Purchase) issuance of stock for Dividend Reinvestment Plan	(1,273)	(1,244)	568
Change in cash overdrafts due to outstanding checks	597	91	3,255
Net borrowing (repayment) under line of credit agreements	25,894	(241)	1,579
Other short-term borrowing		(29,100)	29,100
Proceeds from issuance of long-term debt		29,000
Repayment of long-term debt	(8,202)	(9,134)	(36,860)
Net cash provided (used) by financing activities	4,681	(22,291)	(13,371)
Net Increase (Decrease) in Cash and Cash Equivalents	724	994	(1,175)
Cash and Cash Equivalents - Beginning of Period	2,637	1,643	2,818
Cash and Cash Equivalents - End of Period	$ 3,361	$ 2,637	$ 1,643