Consolidated Balance Sheets (Parenthetical) - SPPC - $ / shares	Jun. 30, 2019	Dec. 31, 2018
Common stock, shares authorized	115,000,000	115,000,000
Common stock, shares issued	77,000,000	77,000,000
Common stock, shares outstanding	77,000,000	77,000,000
Sierra Pacific Power Company [Member]
Common Stock, Par or Stated Value Per Share	$ 3.75	$ 3.75
Common stock, shares authorized	20,000,000	20,000,000
Common stock, shares issued	1,000	1,000
Common stock, shares outstanding	1,000	1,000