XML 49 R42.htm IDEA: XBRL DOCUMENT v3.24.1.u1
Fair Value Measurements - Summary of Financial Instrument Measured at Fair Value On A Recurring Basis and Carrying Amount and Fair Value (Details) - USD ($)
$ in Millions
Mar. 31, 2024
Dec. 31, 2023
OGE Energy Term Loan [Member]    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Total long-term debt $ 49.9 $ 49.9
Long-Term Debt, Fair Value 50.0 50.0
OG&E Senior Notes [Member]    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Total long-term debt 4,146.8 4,146.0
Long-Term Debt, Fair Value 3,868.5 3,922.3
OG&E Industrial Authority Bonds [Member]    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Total long-term debt 135.4 135.4
Long-Term Debt, Fair Value 135.4 135.4
OG&E Tinker Debt [Member]    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Total long-term debt 9.2 9.2
Long-Term Debt, Fair Value $ 7.0 $ 7.1