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Unaudited Financial Information (Table) | 9 Months Ended
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Jun. 30, 2017
Regulatory Assets And Liabilities Table [Abstract] |
Schedule Of Regulatory Assets And Liabilities [Table Text Block] | Significant regulatory assets and liabilities as of June 30, 2017 and September 30, 2016 included the following:
| June 30, 2017 |  | September 30, 2016
| (In thousands)
Regulatory assets: |  |  |
Pension and postretirement benefit costs(1) | $ | 122,202 |  |  | $ | 132,348 |
Infrastructure mechanisms(2) | 38,653 |  |  | 42,719 |
Deferred gas costs | 16,405 |  |  | 45,184 |
Recoverable loss on reacquired debt | 11,843 |  |  | 13,761 |
Deferred pipeline record collection costs | 10,327 |  |  | 7,336 |
APT annual adjustment mechanism | 4,973 |  |  | 7,171 |
Rate case costs | 2,480 |  |  | 1,539 |
Other | 9,949 |  |  | 13,565 |
| $ | 216,832 |  |  | $ | 263,623 |
Regulatory liabilities: |  |  |
Regulatory cost of removal obligations | $ | 492,404 |  |  | $ | 476,891 |
Deferred gas costs | 16,753 |  |  | 20,180 |
Asset retirement obligations | 13,404 |  |  | 13,404 |
Other | 6,729 |  |  | 4,250 |
| $ | 529,290 |  |  | $ | 514,725 |
(1) | Includes $11.5 million and $12.4 million of pension and postretirement expense deferred pursuant to regulatory authorization.
(2) | Infrastructure mechanisms in Texas and Louisiana allow for the deferral of all eligible expenses associated with capital expenditures incurred pursuant to these rules, including the recording of interest on deferred expenses until the next rate proceeding (rate case or annual rate filing), at which time investment and costs would be recoverable through base rates.

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- Definition Tabular disclosure of regulatory assets and liabilities, including current and noncurrent assets created when regulatory agencies permit the deferral of costs to the balance sheet that would otherwise be required to appear on the company's income statement and would be charged against current expenses or revenues, as well as current and noncurrent liabilities that result from rate actions of a regulator. + References No definition available. + Details
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- References No definition available. + Details
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