CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Operating activities
Net income (loss)	$ 1,575	$ (5,476)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	15,736	16,564
Change in value of life insurance contracts	(161)	(158)
Changes in operating assets and liabilities:
Receivables	600us-gaap_IncreaseDecreaseInReceivables	6,006us-gaap_IncreaseDecreaseInReceivables
Accounts payable	(419)	178
Other current assets	(4,604)	(5,065)
Other current liabilities	7,627	7,458
Other changes in noncurrent assets and liabilities	6,535	(9,034)
Net cash provided by operating activities	26,889	10,473
Investing activities:
Utility plant expenditures	(35,047)	(24,620)
Purchase of life insurance		(1,674)
Changes in restricted cash and other changes, net	(26)	418
Net cash (used in) investing activities	(35,073)	(25,876)
Financing activities:
Short-term borrowings	30,000us-gaap_ProceedsFromShortTermDebt	22,200us-gaap_ProceedsFromShortTermDebt
Repayment of short-term borrowings		(5,000)us-gaap_RepaymentsOfShortTermDebt
Issuance of long-term debt	50
Repayment of long-term debt	(338)us-gaap_RepaymentsOfLongTermDebt	(460)us-gaap_RepaymentsOfLongTermDebt
Advances and contributions in aid of construction	1,777	2,194
Refunds of advances for construction	(1,574)	(1,535)
Dividends paid	(8,007)us-gaap_PaymentsOfDividendsCommonStock	(7,758)us-gaap_PaymentsOfDividendsCommonStock
Net cash provided by financing activities	21,908	9,641
Change in cash and cash equivalents	13,724	(5,762)
Cash and cash equivalents at beginning of period	19,587	27,506
Cash and cash equivalents at end of period	33,311	21,744
Supplemental information
Cash paid for interest (net of amounts capitalized)	749us-gaap_InterestPaidNet	837us-gaap_InterestPaidNet
Supplemental disclosure of non-cash activities:
Accrued payables for investments in utility plant	14,374	10,690
Utility plant contribution by developers	$ 1,823	$ 1,020

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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The amount of cash paid for interest during the period net of cash paid for interest that is capitalized.

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The change in cash surrender or contract value during the period which adjusted the amount of premiums paid in determining the expense or income recognized under the contract for the period.

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The increase (decrease) in cash associated with the entity's continuing operating, investing, and financing activities. While for technical reasons this element has no balance attribute, the default assumption is a debit balance consistent with its label.

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Amount of cash inflow (outflow) of investing activities, excluding discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, excluding discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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The cash outflow for payments to purchase life insurance policies for which the entity is the beneficiary.

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