Business Acquisitions (Notes)	3 Months Ended
Business Acquisitions (Notes)	Mar. 31, 2017
Business Acquisitions [Abstract]
Business Combination Disclosure [Text Block]	Business Acquisitions The Company completed various acquisitions totaling $579 million, net of cash acquired, for the three-month period ended March 31, 2017. The purchase price for each acquisition was allocated to the assets acquired and liabilities assumed, which related primarily to development and construction costs for the 110-megawatt Alamo 6 solar-powered generation project, the remaining 25% interest in the Silverhawk natural gas-fueled generation facility at Nevada Power and a residential real estate brokerage business. There were no other material assets acquired or liabilities assumed.

The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).

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