XML 107 R90.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Business segment data (Details) (USD $) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2012 | Sep. 30, 2012 | Jun. 30, 2012 | Mar. 31, 2012 | Dec. 31, 2011 | Sep. 30, 2011 | Jun. 30, 2011 | Mar. 31, 2011 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total external operating revenues | $ 1,081,144,000 |  | $ 1,173,518,000 | $ 967,962,000 |  | $ 852,807,000 | $ 1,065,749,000 |  | $ 1,152,181,000 | $ 930,757,000 | $ 901,805,000 | $ 4,075,431,000 |  | $ 4,050,492,000 |  | $ 3,909,695,000 |
Total intersegment operating revenues |  |  |  |  |  |  |  |  |  |  |  | 0 |  | 0 |  | 0 |
Depreciation, depletion and amortization |  |  |  |  |  |  |  |  |  |  |  | 359,205,000 |  | 343,395,000 |  | 328,843,000 |
Interest expense |  |  |  |  |  |  |  |  |  |  |  | 76,699,000 |  | 81,354,000 |  | 83,011,000 |
Income taxes |  |  |  |  |  |  |  |  |  |  |  | (31,146,000) |  | 110,274,000 |  | 122,530,000 |
Earnings (loss) on common stock before income (loss) from discontinued operations |  |  |  |  |  |  |  |  |  |  |  | (15,006,000) |  | 225,267,000 |  | 243,335,000 |
Income (loss) from discontinued operations, net of tax | 8,700,000 | [1] | (139,000) | 5,106,000 | [2] | (100,000) | (13,080,000) | [1] | (126,000) | (168,000) | 448,000 | 13,567,000 | [3] | (12,926,000) | [3] | (3,361,000) | [3]
Total earnings (loss) on common stock |  |  |  |  |  |  |  |  |  |  |  | (1,439,000) |  | 212,341,000 |  | 239,974,000 |
Net proceeds from sale or disposition of property and other |  |  |  |  |  |  |  |  |  |  |  | (57,460,000) |  | (40,857,000) |  | (78,761,000) |
Total net capital expenditures |  |  |  |  |  |  |  |  |  |  |  | 933,777,000 |  | 481,023,000 |  | 495,246,000 |
Total assets | 6,682,491,000 |  |  |  |  |  | 6,556,125,000 |  |  |  |  | 6,682,491,000 |  | 6,556,125,000 |  | 6,303,549,000 |
Property, plant and equipment | 8,107,751,000 |  |  |  |  |  | 7,646,222,000 |  |  |  |  | 8,107,751,000 |  | 7,646,222,000 |  |  |
Less accumulated depreciation, depletion and amortization | 3,608,912,000 |  |  |  |  |  | 3,361,208,000 |  |  |  |  | 3,608,912,000 |  | 3,361,208,000 |  | 3,103,323,000 |
Net property, plant and equipment | 4,498,839,000 |  |  |  |  |  | 4,285,014,000 |  |  |  |  | 4,498,839,000 |  | 4,285,014,000 |  | 4,115,180,000 |
Additional information [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Write-downs of oil and natural gas properties | 231,700,000 |  | 160,100,000 |  |  |  |  |  |  |  |  | 391,800,000 |  | 0 |  | 0 |
Noncash write-down of natural gas and oil properties, after tax | 145,900,000 |  | 100,900,000 |  |  |  |  |  |  |  |  | 246,800,000 |  |  |  |  |
Natural gas gathering arbitration charge, after tax |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 16,500,000 |
Reversal of an arbitration charge after tax |  |  |  | 15,000,000 |  |  |  |  |  |  |  | 15,000,000 |  |  |  |  |
Net noncash transactions included in capital expenditures |  |  |  |  |  |  |  |  |  |  |  | 33,700,000 |  | 24,000,000 |  | 17,500,000 |
Regulated: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total external operating revenues |  |  |  |  |  |  |  |  |  |  |  | 1,131,626,000 |  | 1,343,714,000 |  | 1,359,028,000 |
Nonregulated: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total external operating revenues |  |  |  |  |  |  |  |  |  |  |  | 2,943,805,000 |  | 2,706,778,000 |  | 2,550,667,000 |
Electric: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total external operating revenues |  |  |  |  |  |  |  |  |  |  |  | 236,895,000 |  | 225,468,000 |  | 211,544,000 |
Total intersegment operating revenues |  |  |  |  |  |  |  |  |  |  |  | 0 |  | 0 |  | 0 |
Depreciation, depletion and amortization |  |  |  |  |  |  |  |  |  |  |  | 32,509,000 |  | 32,177,000 |  | 27,274,000 |
Interest expense |  |  |  |  |  |  |  |  |  |  |  | 12,421,000 |  | 13,745,000 |  | 12,216,000 |
Income taxes |  |  |  |  |  |  |  |  |  |  |  | 8,975,000 |  | 7,242,000 |  | 11,187,000 |
Earnings (loss) on common stock before income (loss) from discontinued operations |  |  |  |  |  |  |  |  |  |  |  | 30,634,000 |  | 29,258,000 |  | 28,908,000 |
Capital expenditures |  |  |  |  |  |  |  |  |  |  |  | 112,035,000 |  | 52,072,000 |  | 85,787,000 |
Total assets | 760,324,000 | [4] |  |  |  |  | 672,940,000 | [4] |  |  |  | 760,324,000 | [4] | 672,940,000 | [4] | 643,636,000 | [4]
Property, plant and equipment | 1,150,584,000 | [4] |  |  |  |  | 1,068,524,000 | [4] |  |  |  | 1,150,584,000 | [4] | 1,068,524,000 | [4] | 1,027,034,000 | [4]
Natural gas distribution: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total external operating revenues |  |  |  |  |  |  |  |  |  |  |  | 754,848,000 |  | 907,400,000 |  | 892,708,000 |
Total intersegment operating revenues |  |  |  |  |  |  |  |  |  |  |  | 0 |  | 0 |  | 0 |
Depreciation, depletion and amortization |  |  |  |  |  |  |  |  |  |  |  | 45,731,000 |  | 44,641,000 |  | 43,044,000 |
Interest expense |  |  |  |  |  |  |  |  |  |  |  | 28,726,000 |  | 29,444,000 |  | 28,996,000 |
Income taxes |  |  |  |  |  |  |  |  |  |  |  | 12,005,000 |  | 16,931,000 |  | 12,171,000 |
Earnings (loss) on common stock before income (loss) from discontinued operations |  |  |  |  |  |  |  |  |  |  |  | 29,409,000 |  | 38,398,000 |  | 36,944,000 |
Capital expenditures |  |  |  |  |  |  |  |  |  |  |  | 130,178,000 |  | 70,624,000 |  | 75,365,000 |
Total assets | 1,703,459,000 | [4] |  |  |  |  | 1,679,091,000 | [4] |  |  |  | 1,703,459,000 | [4] | 1,679,091,000 | [4] | 1,632,012,000 | [4]
Property, plant and equipment | 1,689,950,000 | [4] |  |  |  |  | 1,568,866,000 | [4] |  |  |  | 1,689,950,000 | [4] | 1,568,866,000 | [4] | 1,508,845,000 | [4]
Pipeline and energy services: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total external operating revenues |  |  |  |  |  |  |  |  |  |  |  | 139,883,000 |  | 210,846,000 |  | 254,776,000 |
Total intersegment operating revenues |  |  |  |  |  |  |  |  |  |  |  | 53,274,000 |  | 67,497,000 |  | 75,033,000 |
Depreciation, depletion and amortization |  |  |  |  |  |  |  |  |  |  |  | 27,684,000 |  | 25,502,000 |  | 26,001,000 |
Interest expense |  |  |  |  |  |  |  |  |  |  |  | 7,742,000 |  | 10,516,000 |  | 9,064,000 |
Income taxes |  |  |  |  |  |  |  |  |  |  |  | 15,291,000 |  | 12,912,000 |  | 13,933,000 |
Earnings (loss) on common stock before income (loss) from discontinued operations |  |  |  |  |  |  |  |  |  |  |  | 26,588,000 |  | 23,082,000 |  | 23,208,000 |
Capital expenditures |  |  |  |  |  |  |  |  |  |  |  | 133,787,000 |  | 45,556,000 |  | 14,255,000 |
Total assets | 622,470,000 |  |  |  |  |  | 526,797,000 |  |  |  |  | 622,470,000 |  | 526,797,000 |  | 523,075,000 |
Property, plant and equipment | 816,533,000 |  |  |  |  |  | 719,291,000 |  |  |  |  | 816,533,000 |  | 719,291,000 |  | 683,807,000 |
Exploration and production: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total external operating revenues |  |  |  |  |  |  |  |  |  |  |  | 412,651,000 |  | 359,873,000 |  | 318,570,000 |
Total intersegment operating revenues |  |  |  |  |  |  |  |  |  |  |  | 35,966,000 |  | 93,713,000 |  | 115,784,000 |
Depreciation, depletion and amortization |  |  |  |  |  |  |  |  |  |  |  | 160,681,000 |  | 142,645,000 |  | 130,455,000 |
Interest expense |  |  |  |  |  |  |  |  |  |  |  | 9,018,000 |  | 7,445,000 |  | 8,580,000 |
Income taxes |  |  |  |  |  |  |  |  |  |  |  | (108,264,000) |  | 46,298,000 |  | 49,034,000 |
Earnings (loss) on common stock before income (loss) from discontinued operations |  |  |  |  |  |  |  |  |  |  |  | (177,283,000) |  | 80,282,000 |  | 85,638,000 |
Capital expenditures |  |  |  |  |  |  |  |  |  |  |  | 554,528,000 |  | 272,855,000 |  | 355,845,000 |
Total assets | 1,539,017,000 |  |  |  |  |  | 1,481,556,000 |  |  |  |  | 1,539,017,000 |  | 1,481,556,000 |  | 1,342,808,000 |
Property, plant and equipment | 2,764,560,000 |  |  |  |  |  | 2,615,146,000 |  |  |  |  | 2,764,560,000 |  | 2,615,146,000 |  | 2,356,938,000 |
Construction materials and contracting: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total external operating revenues |  |  |  |  |  |  |  |  |  |  |  | 1,597,257,000 |  | 1,509,538,000 |  | 1,445,148,000 |
Total intersegment operating revenues |  |  |  |  |  |  |  |  |  |  |  | 20,168,000 |  | 472,000 |  | 0 |
Depreciation, depletion and amortization |  |  |  |  |  |  |  |  |  |  |  | 79,527,000 |  | 85,459,000 |  | 88,331,000 |
Interest expense |  |  |  |  |  |  |  |  |  |  |  | 15,211,000 |  | 16,241,000 |  | 19,859,000 |
Income taxes |  |  |  |  |  |  |  |  |  |  |  | 14,099,000 |  | 11,227,000 |  | 13,822,000 |
Earnings (loss) on common stock before income (loss) from discontinued operations |  |  |  |  |  |  |  |  |  |  |  | 32,420,000 |  | 26,430,000 |  | 29,609,000 |
Capital expenditures |  |  |  |  |  |  |  |  |  |  |  | 45,083,000 |  | 52,303,000 |  | 25,724,000 |
Total assets | 1,371,252,000 |  |  |  |  |  | 1,374,026,000 |  |  |  |  | 1,371,252,000 |  | 1,374,026,000 |  | 1,382,836,000 |
Property, plant and equipment | 1,504,981,000 |  |  |  |  |  | 1,499,852,000 |  |  |  |  | 1,504,981,000 |  | 1,499,852,000 |  | 1,486,375,000 |
Construction services: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total external operating revenues |  |  |  |  |  |  |  |  |  |  |  | 932,013,000 |  | 834,918,000 |  | 786,802,000 |
Total intersegment operating revenues |  |  |  |  |  |  |  |  |  |  |  | 6,545,000 |  | 19,471,000 |  | 2,298,000 |
Depreciation, depletion and amortization |  |  |  |  |  |  |  |  |  |  |  | 11,063,000 |  | 11,399,000 |  | 12,147,000 |
Interest expense |  |  |  |  |  |  |  |  |  |  |  | 4,435,000 |  | 4,473,000 |  | 4,411,000 |
Income taxes |  |  |  |  |  |  |  |  |  |  |  | 24,128,000 |  | 13,426,000 |  | 11,456,000 |
Earnings (loss) on common stock before income (loss) from discontinued operations |  |  |  |  |  |  |  |  |  |  |  | 38,429,000 |  | 21,627,000 |  | 17,982,000 |
Capital expenditures |  |  |  |  |  |  |  |  |  |  |  | 14,835,000 |  | 9,711,000 |  | 14,849,000 |
Total assets | 429,547,000 |  |  |  |  |  | 418,519,000 |  |  |  |  | 429,547,000 |  | 418,519,000 |  | 387,627,000 |
Property, plant and equipment | 130,624,000 |  |  |  |  |  | 124,796,000 |  |  |  |  | 130,624,000 |  | 124,796,000 |  | 122,940,000 |
Other [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total external operating revenues |  |  |  |  |  |  |  |  |  |  |  | 1,884,000 |  | 2,449,000 |  | 147,000 |
Total intersegment operating revenues |  |  |  |  |  |  |  |  |  |  |  | 8,486,000 |  | 8,997,000 |  | 7,580,000 |
Depreciation, depletion and amortization |  |  |  |  |  |  |  |  |  |  |  | 2,010,000 |  | 1,572,000 |  | 1,591,000 |
Interest expense |  |  |  |  |  |  |  |  |  |  |  | 13,000 |  | 0 |  | 47,000 |
Income taxes |  |  |  |  |  |  |  |  |  |  |  | 2,620,000 |  | 2,238,000 |  | 10,927,000 |
Earnings (loss) on common stock before income (loss) from discontinued operations |  |  |  |  |  |  |  |  |  |  |  | 4,797,000 |  | 6,190,000 |  | 21,046,000 |
Capital expenditures |  |  |  |  |  |  |  |  |  |  |  | 791,000 |  | 18,759,000 |  | 2,182,000 |
Total assets | 256,422,000 | [5] |  |  |  |  | 403,196,000 | [5] |  |  |  | 256,422,000 | [5] | 403,196,000 | [5] | 391,555,000 | [5]
Property, plant and equipment | 50,519,000 |  |  |  |  |  | 49,747,000 |  |  |  |  | 50,519,000 |  | 49,747,000 |  | 32,564,000 |
Intersegment Elimination [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total intersegment operating revenues |  |  |  |  |  |  |  |  |  |  |  | (124,439,000) |  | (190,150,000) |  | (200,695,000) |
Interest expense |  |  |  |  |  |  |  |  |  |  |  | $ (867,000) |  | $ (510,000) |  | $ (162,000) |
[1] | 2012 reflects a $145.9 million after-tax noncash write-down of oil and natural gas properties and the reversal of an arbitration charge of $13.0 million (after tax) related to a guarantee of a construction contract, which was partially offset by the reversal of estimated insurance recoveries, as previously discussed. 2011 reflects an arbitration charge of $13.0 million (after tax) related to a guarantee of a construction contract. For more information, see Notes 1 and 19, respectively.
[2] | 2012 reflects a net benefit of $15.0 million (after tax) related to natural gas gathering operations litigation and a net benefit largely related to estimated insurance recoveries related to the guarantee of a construction contract. For more information, see Note 19.
[3] | Reflected in the Other category.
[4] | Includes allocations of common utility property.
[5] | Includes assets not directly assignable to a business (i.e. cash and cash equivalents, certain accounts receivable, certain investments and other miscellaneous current and deferred assets).

X
- Definition Earnings Loss On Common Stock before loss from discontinued operations + References No definition available. + Details
Name: | mdu_EarningsLossOnCommonStockBeforeLossFromDiscontinuedOperations
Namespace Prefix: | mdu_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The after tax expense recorded to reduce the value of oil and gas assets consisting of proved properties and unproved properties as the estimate of future successful production from these properties is reduced. + References No definition available. + Details
Name: | mdu_ImpairmentOfOilAndGasPropertiesAfterTax
Namespace Prefix: | mdu_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Natural gas gathering arbitration charge, after tax. + References No definition available. + Details
Name: | mdu_NaturalGasGatheringArbitrationChargeAfterTax
Namespace Prefix: | mdu_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Net noncash transactions included in capital expenditures. + References No definition available. + Details
Name: | mdu_NetNoncashTransactionsIncludedInCapitalExpenditures
Namespace Prefix: | mdu_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Reversal of an arbitration charge after tax. + References No definition available. + Details
Name: | mdu_ReversalOfArbitrationChargeAfterTax
Namespace Prefix: | mdu_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 14 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 5 -Subparagraph c -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 5 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.14) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 + Details
Name: | us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 12 -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Concepts (CON) -Number 6 -Paragraph 25 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 18 -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.18) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_Assets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585 + Details
Name: | us-gaap_DepreciationDepletionAndAmortization
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The expense recorded to reduce the value of oil and gas assets consisting of proved properties and unproved properties as the estimate of future successful production from these properties is reduced. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 27, 28, 29 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 360 -Section 35 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=6475018&loc=d3e66150-109466 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2921-110230 + Details
Name: | us-gaap_ImpairmentOfOilAndGasProperties
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of income (loss) from a disposal group, net of income tax before extraordinary items allocable to noncontrolling interests. Includes, net of tax, income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e957-107759 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 144 -Paragraph 47 -Subparagraph c -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Article 5 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 29 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.14) -URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 144 -Paragraph 43 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.12) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 + Details
Name: | us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a),(b) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 45 -Subparagraph a, b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)) -URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Article 4 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Income Tax Expense (or Benefit) -URI http://asc.fasb.org/extlink&oid=6515339 + Details
Name: | us-gaap_IncomeTaxExpenseBenefit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The cost of borrowed funds accounted for as interest that was charged against earnings during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 9 -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Section 563c.102 -Paragraph 9 -Chapter V -Subsection II -LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 34 -Paragraph 21 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.9) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 + Details
Name: | us-gaap_InterestExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1377-109256 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 9 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
Name: | us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Acquisition of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
Name: | us-gaap_PropertyPlantAndEquipmentAdditions
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Divestiture of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
Name: | us-gaap_PropertyPlantAndEquipmentDisposals
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Gross amount of long-lived physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 5 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_PropertyPlantAndEquipmentGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Property, plant and equipment additions minus disposals plus or minus transfers and other changes equals the increase or decrease in property, plant and equipment for the period. + References No definition available. + Details
Name: | us-gaap_PropertyPlantAndEquipmentGrossPeriodIncreaseDecrease
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, net of accumulated depreciation, depletion and amortization, of long-lived physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 8 -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 12 -Paragraph 5 -Subparagraph b, c -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 13 -Subparagraph a -Article 5 + Details
Name: | us-gaap_PropertyPlantAndEquipmentNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Article 5 + Details
Name: | us-gaap_Revenues
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of revenue from transactions with other operating segments of the same entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 27 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
Name: | us-gaap_RevenuesFromTransactionsWithOtherOperatingSegmentsOfSameEntity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_SegmentReportingInformationAdditionalInformationAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_SegmentReportingInformationLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration