| **Consolidated Statements Of Cash Flow - USD ($) $ in Thousands**                                                                        | 3 Months Ended |
|------------------------------------------------------------------------------------------------------------------------------------------|----------------|
||
| **Cash flows from operating activities:**                                                                                                |           |   |
| Net income                                                                                                                               | $ 16,924       | $ 50,839 |
| **Adjustments to reconcile net income to net cash flows from operating activities:**                                                     |           |   |
| Depreciation and amortization                                                                                                            | 39,410         | 36,097 |
| Deferred income taxes                                                                                                                    | (8,852)        | (2,849) |
| Provision for doubtful accounts                                                                                                          | 803            | 896 |
| Stock-based compensation                                                                                                                 | 1,930          | 1,444 |
| Gain on sale of other assets                                                                                                             | (220)          | (196) |
| Interest rate swap agreements                                                                                                            | 34,782         |  |
| Net change in receivables, inventory and prepayments                                                                                     | 2,263          | 5,402 |
| Net change in payables, accrued interest, accrued taxes and other accrued liabilities                                                    | (3,402)        | (996) |
| Pension and other postretirement benefits contributions                                                                                  | (3,947)        | (5,217) |
| Other                                                                                                                                    | (404)          | 2,934 |
| Net cash flows from operating activities                                                                                                 | 79,287         | 88,354 |
| **Cash flows from investing activities:**                                                                                                |           |   |
| Property, plant and equipment additions, including the debt component of allowance for funds used during construction of $1,030 and $782 | (133,792)      | (105,136) |
| Acquisitions of utility systems, net                                                                                                     | (469)          | (190) |
| Net proceeds from the sale of other assets                                                                                               | 242            | 174 |
| Other                                                                                                                                    | 462            | (75) |
| Net cash flows used in investing activities                                                                                              | (133,557)      | (105,227) |
| **Cash flows from financing activities:**                                                                                                |           |   |
| Customers' advances and contributions in aid of construction                                                                             | 1,858          | 1,742 |
| Repayments of customers' advances                                                                                                        | (765)          | (1,014) |
| Net proceeds of short-term debt                                                                                                          | 17,114         | 16,692 |
| Proceeds from long-term debt                                                                                                             | 117,995        | 66,996 |
| Repayments of long-term debt                                                                                                             | (41,976)       | (21,898) |
| Change in cash overdraft position                                                                                                        | (3,856)        | (8,944) |
| Proceeds from issuing common stock                                                                                                       | 4,035          | 361 |
| Proceeds from exercised stock options                                                                                                    | 1,175          | 1,010 |
| Repurchase of common stock                                                                                                               | (1,857)        | (2,491) |
| Dividends paid on common stock                                                                                                           | (39,014)       | (36,386) |
| Other                                                                                                                                    | (13)           | (197) |
| Net cash flows from financing activities                                                                                                 | 54,696         | 15,871 |
| Net change in cash and cash equivalents                                                                                                  | 426            | (1,002) |
| Cash and cash equivalents at beginning of period                                                                                         | 3,627          | 4,204 |
| Cash and cash equivalents at end of period                                                                                               | 4,053          | 3,202 |
| **Non-cash investing activities:**                                                                                                       |           |   |
| Property, plant and equipment additions purchased at the period end, but not yet paid for                                                | 42,594         | 23,629 |
| Non-cash customer advances and contributions in aid of construction                                                                      | $ 17,331       | $ 4,979 |

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Future cash outflow to pay for purchases of fixed assets that have occurred.
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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, 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.
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Amount of increase (decrease) in cash, cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; including effect from exchange rate change. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, 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.
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Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.
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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.
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Amount of gain (loss) on sale or disposal of other assets.
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The increase (decrease) during the reporting period in the amounts payable to vendors for goods and services received and the amount of obligations and expenses incurred but not paid.
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Amount of increase (decrease) in operating assets classified as other.
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Amount of increase (decrease) in obligation for pension and other postretirement benefits. Includes, but is not limited to, defined benefit and defined contribution plans.
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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.
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Amount of cash inflow (outflow) from investing activities, including 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, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.
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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.
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Amount of cash (inflow) outflow from investing activities classified as other.
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The cash outflow to reacquire common stock during 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 acquisition of buildings (properties) whether for investment or use.
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The cash outflow for the purchase of waste water systems which includes the waste treatment and disposal facility and equipment to households and industry.
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The cash inflow from the additional capital contribution to the entity.
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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.
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Amount of cash inflow (outflow) from financing activities classified as other.
+ References
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| - Definition
The net cash inflow or outflow from the excess drawing from an existing cash balance, which will be honored by the bank but reflected as a loan to the drawer.
+ References
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| - Definition
The cash inflow from a borrowing having initial term of repayment within one year or the normal operating cycle, if longer.
+ References
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| - Definition
Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.
+ References
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| - Definition
Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.
+ References
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| - Definition
The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.
+ References
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| - Definition
The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.
+ References
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| - Definition
The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of investments, not including unrealized gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, held at each balance sheet date and included in earnings for the period.
+ References
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| - Definition
Increase (Decrease) in Inventories, Receivables, And Prepayments
+ References
No definition available.
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| - Definition
Non-Cash Customer Advances And Contributions In Aid Of Construction
+ References
No definition available.
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| - Definition
Proceeds from Advances for Construction, Financing Activities
+ References
No definition available.
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| - Definition
Proceeds from sale of utility system and other
+ References
No definition available.
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| - Definition
Repayments of Advances for Construction, Financing Activities
+ References
No definition available.
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