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Summary of Significant Accounting Policies - Investments in Affiliates and Other Entities (Detail) - Capital for infrastructure projects $ in Millions | Sep. 30, 2017 USD ($)
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Summary Of Significant Accounting Policies [Line Items] |
Other commitment | $ 80.0
Infrastructure investors partnership |
Summary Of Significant Accounting Policies [Line Items] |
Other commitment | $ 1,000.0

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- Definition Summary Of Significant Accounting Policies [Line Items] + References No definition available. + Details
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- Definition Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions. + References No definition available. + Details
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- Details
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- Details
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