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Pronghorn (Details) - Pronghorn [Member] - USD ($) $ in Millions | Jan. 01, 2017 | Nov. 21, 2016
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Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |
Percent of ownership to sell |  | 50.00%
Pronghorn [Member] |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |
Proceeds | $ 100 |

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- Definition Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation. + References No definition available. + Details
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Balance Type: | debit
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X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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X
- Details
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Namespace Prefix: |
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