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Commitments and Contingencies - Outstanding Capital Commitments Associated with Investments in Unconsolidated Affiliates (Parenthetical) (Detail) $ in Millions | 1 Months Ended
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Aug. 31, 2017 USD ($)
Other Commitments, Engineering, Procurement and Construction Electric Transmission Project [Member] | Corporate Joint Venture [Member] | Scenario Forecast [Member] |
Other Commitments [Line Items] |
Return of capital from unconsolidated affiliates anticipated for 2017 | $ 43.1

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- 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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- Definition Cash dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporations that are returns of capital. Excludes dividends or distributions from equity method investments classified as operating activities. + References No definition available. + Details
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