XML 158 R201.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
Income Taxes - NPC - Reconciliation of Effective Income Tax Rate (Details)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Income Tax Contingency [Line Items]      
Federal statutory income tax rate 21.00% 21.00% 35.00%
Effective Income Tax Rate Reconciliation Regulatory Differences 6.00% 8.00% 1.00%
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount 0.00% 4.00% 31.00%
Other, net (1.00%) (1.00%) (1.00%)
Effective income tax rate (25.00%) (30.00%) (22.00%)
Nevada Power Company [Member]      
Income Tax Contingency [Line Items]      
Federal statutory income tax rate 21.00% 21.00% 35.00%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Merger Charges, Percent 0.00% 3.00% 0.00%
Effective Income Tax Rate Reconciliation Regulatory Differences 0.00% 0.00% 1.00%
Other, net 1.00% 0.00% 1.00%
Effective income tax rate 22.00% 24.00% 38.00%
Tax Cuts and Jobs Act of 2017 [Member]      
Income Tax Contingency [Line Items]      
Federal statutory income tax rate 21.00% 21.00%  
Tax Cuts and Jobs Act of 2017 [Member] | Nevada Power Company [Member]      
Income Tax Contingency [Line Items]      
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount 0.00% 0.00% 1.00%