Regulatory Matters Regulatory Matters - NPC (Details) - Nevada Power Company [Member] - Public Utilities Commission, Nevada [Member] - USD ($) $ in Millions	1 Months Ended
Jun. 30, 2019	Oct. 31, 2018
Stations Casinos LLC [Member]
Schedule Of Regulatory Assets and Liabilities [Line Items]
Total impact fee		$ 15
Boyd Gaming Corporation [Member]
Schedule Of Regulatory Assets and Liabilities [Line Items]
Total impact fee	$ 11

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.

No definition available.

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