XML 42 R31.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Divestitures and Acquisitions (Tables) | 6 Months Ended
--- | ---
Mar. 31, 2018
Divestitures and Acquisitions [Abstract] |
Disposal Groups, Including Discontinued Operations [Table Text Block] | The following table presents statement of income data related to discontinued operations:
| Six Months Ended March 31, 2017
| (In thousands)
Operating revenues | $ | 303,474 |
Purchased gas cost | 277,554 |
Operating expenses | 7,874 |
Operating income | 18,046 |
Other nonoperating expense | (211 | )
Income from discontinued operations before income taxes | 17,835 |
Income tax expense | 6,841 |
Income from discontinued operations | 10,994 |
Gain on sale from discontinued operations, net of tax ($10,215) | 2,716 |
Net income from discontinued operations | $ | 13,710 |
The following table presents statement of cash flow data related to discontinued operations:
| Six Months Ended March 31, 2017
| (In thousands)
Depreciation and amortization expense | $ | 185 |
Capital expenditures | $ | — |
Non-cash loss in commodity contract cash flow hedges | $ | (8,165 | )
Fair value hedges table | The impact of our natural gas marketing segment commodity contracts designated as fair value hedges and the related hedged item on the results of discontinued operations on our condensed consolidated income statement for the six months ended March 31, 2017 is presented below.
| Six Months Ended March 31, 2017
| (In thousands)
Commodity contracts | $ | (9,567 | )
Fair value adjustment for natural gas inventory designated as the hedged item | 12,858 |
Total decrease in purchased gas cost reflected in income from discontinued operations | $ | 3,291 |
The decrease in purchased gas cost reflected in income from discontinued operations is comprised of the following: |
Basis ineffectiveness | $ | (597 | )
Timing ineffectiveness | 3,888 |
| $ | 3,291 |
Cash flow hedges | The impact of our natural gas marketing segment cash flow hedges on our condensed consolidated income statements for the six months ended March 31, 2017 is presented below:
| Six Months Ended March 31, 2017
| (In thousands)
Loss reclassified from AOCI for effective portion of natural gas marketing commodity contracts | $ | (2,612 | )
Gain arising from ineffective portion of natural gas marketing commodity contracts | 111 |
Gain on discontinuance of cash flow hedging of natural gas marketing commodity contracts reclassified from AOCI | 10,579 |
Total impact on purchased gas cost reflected in income from discontinued operations | $ | 8,078 |

X
- Definition Divestitures and Acquisitions [Abstract] + References No definition available. + Details
Name: | ato_DivestituresandAcquisitionsAbstract
Namespace Prefix: | ato_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure for cash flow hedging instruments of (a) the location and amount of gains and losses reported in the statement of financial performance and (b) the location and fair value amounts of the instruments reported in the statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 + Details
Name: | us-gaap_ScheduleOfCashFlowHedgingInstrumentsStatementsOfFinancialPerformanceAndFinancialPositionLocationTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of information related to a disposal group. Includes, but is not limited to, a discontinued operation, disposal classified as held-for-sale or disposed of by means other than sale or disposal of an individually significant component. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=65878427&loc=SL51721533-107759 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 4B -URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721665-107760 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=64827811&loc=d3e1474-107760 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=64827811&loc=d3e1361-107760 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721683-107760 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3A -URI http://asc.fasb.org/extlink&oid=84176398&loc=SL51724579-110230 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5C -URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721675-107760 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 4A -URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721663-107760 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84176398&loc=d3e2941-110230 Reference 10: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5B -URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721673-107760 Reference 11: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 3A -URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721659-107760 Reference 12: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5A -URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721671-107760 Reference 13: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5D -URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721677-107760 + Details
Name: | us-gaap_ScheduleOfDisposalGroupsIncludingDiscontinuedOperationsIncomeStatementBalanceSheetAndAdditionalDisclosuresTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure for fair value hedging instruments of (a) the location and amount of gains and losses reported in the statement of financial performance and (b) the location and fair value amounts of the instruments reported in the statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 + Details
Name: | us-gaap_ScheduleOfFairValueHedgingInstrumentsStatementsOfFinancialPerformanceAndFinancialPositionLocationTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration