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Balance Sheet Components Other Current Assets (Details) - USD ($) $ in Millions | Sep. 30, 2018 | Dec. 31, 2017
--- | --- | ---
Other Current Assets [Line Items] |  |
Prepaid expenses | $ 31 | $ 50
Assets from price risk management activities | 5 | 6
Margin deposits | 5 | 11
Other | 10 | 6
Other current assets | $ 51 | $ 73

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- Definition Regulatory assets from price risk management activities + References No definition available. + Details
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- Definition The amount of cash or securities placed with a broker or counterparty as security for a trading or derivatives securities position which was partially obtained with funds provided by the broker dealer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.8,17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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