| **Condensed Consolidated Statements of Income (Unaudited) (USD $)In Millions, except Per Share data** | 3 Months Ended | 9 Months Ended |
|-------------------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Operating revenues**                                                                                |           |           |   |   |
| Gas distribution (includes revenue taxes of $14.4, $14.0, $120.7 and $111.8, respectively)            | $ 239.9        | $ 233.5        | $ 1,514.6 | $ 1,601.8 |
| Shipping                                                                                              | 78.4           | 83.9           | 239.1 | 253.4 |
| Other energy ventures                                                                                 | 35.8           | 41.2           | 147.3 | 157.2 |
| Corporate and eliminations                                                                            | (5.7)          | (6.1)          | (38.6) | (41.4) |
| Total operating revenues                                                                              | 348.4          | 352.5          | 1,862.4 | 1,971.0 |
| **Operating expenses**                                                                                |           |           |   |   |
| Gas distribution - Cost of gas                                                                        | 92.9           | 75.5           | 914.7 | 982.3 |
| Gas distribution - Operating and maintenance                                                          | 60.0           | 74.2           | 210.0 | 217.1 |
| Gas distribution - Depreciation                                                                       | 47.1           | 45.9           | 141.3 | 137.8 |
| Gas distribution - Taxes, other than income taxes                                                     | 18.6           | 18.3           | 133.5 | 124.4 |
| Gas distribution - Other                                                                              | 0              | (1.3)          | 0 | (1.3) |
| Shipping                                                                                              | 82.1           | 80.3           | 244.3 | 246.1 |
| Other energy ventures                                                                                 | 34.1           | 34.1           | 131.7 | 134.3 |
| Other corporate expenses and eliminations                                                             | (4.7)          | (4.9)          | (32.4) | (39.5) |
| Total operating expenses                                                                              | 330.1          | 322.1          | 1,743.1 | 1,801.2 |
| Operating income                                                                                      | 18.3           | 30.4           | 119.3 | 169.8 |
| Interest expense, net of amounts capitalized                                                          | 8.5            | 9.7            | 24.1 | 28.4 |
| Equity investment income, net                                                                         | 4.3            | 1.5            | 12.0 | 5.1 |
| Other income, net                                                                                     | 0.5            | 0.5            | 1.3 | 1.9 |
| Income before income taxes                                                                            | 14.6           | 22.7           | 108.5 | 148.4 |
| Income tax expense, net of benefits                                                                   | 8.9            | 9.1            | 38.4 | 50.1 |
| Net income                                                                                            | $ 5.7          | $ 13.6         | $ 70.1 | $ 98.3 |
| **Average shares of common stock outstanding**                                                        |           |           |   |   |
| Basic                                                                                                 | 45.9           | 45.7           | 45.9 | 45.6 |
| Diluted                                                                                               | 46.0           | 45.9           | 45.9 | 45.8 |
| **Earnings per average share of common stock**                                                        |           |           |   |   |
| Basic                                                                                                 | $ 0.12         | $ 0.30         | $ 1.52 | $ 2.16 |
| Diluted                                                                                               | $ 0.12         | $ 0.30         | $ 1.52 | $ 2.15 |
| Dividends declared per share of common stock                                                          | $ 0.465        | $ 0.465        | $ 1.395 | $ 1.395 |

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Mercury-related costs (recoveries), reflect the estimated costs, recoveries and reserve adjustments associated with the company's mercury inspection and repair program.
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Sum of operating profit and nonoperating income (expense) before income taxes, extraordinary items, cumulative effects of changes in accounting principles, and noncontrolling interest.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The total amount of operating cost and expense associated with the transporting cargo and freight between locations.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Revenue from transporting cargo and freight between locations.
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Aggregate dividends declared during the period for each share of common stock outstanding.
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| - Definition
The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.
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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.
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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.
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| - Definition
The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.
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| - Definition
The cost of borrowed funds accounted for as interest that was charged against earnings during the period.
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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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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.
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The net result for the period of deducting operating expenses from operating revenues.
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The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation.
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| - Definition
The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.
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| - Definition
Revenues from the sale of other goods or rendering of other services, not elsewhere specified in the taxonomy; net of (reduced by) sales adjustments, returns, allowances, and discounts.
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| - Definition
The total amount of operating revenues recognized during the period.
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| - Definition
The amount of regulated gas operating revenues recognized during the period.
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| - Definition
For a significant segment item of information disclosed (for example, liabilities) other than profit/loss, revenues, or assets, the total of reconciling items between the total over reportable segments of the significant segment item and the consolidated entity total of the significant segment item.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Total of reconciling items between total reportable segments' revenues and consolidated entity revenues.
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| - Definition
Discloses the amount of operating expense for the period related to depreciation and amortization.
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| - Definition
The amount of purchased gas and petroleum charged against earnings for the period.
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| - Definition
Discloses the amount of operating expense for the period for routine plant maintenance, repairs and operations.
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| - Definition
Discloses the amount of operating expense for the period related to taxes other income .
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.
+ References
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