v3.26.1
Investments (Details) - NGSP - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
EBP, Master Trust [Line Items]    
Master trust percentage 99.00% 99.00%
Investment, fair value $ 43,943,483 $ 39,066,279
Total assets 44,357,244 39,473,777
Net assets available for benefits 44,355,185 39,471,854
Net appreciation in value of investments 515,172  
Interest 30,138  
Dividends 104,944  
Investment manager fees (3,500)  
Total investment income 6,602,923  
Master Trust Balances    
EBP, Master Trust [Line Items]    
Investment, fair value 36,953,901 33,060,233
Investment, contract value 3,052,155 3,161,481
Dividends, interest, taxes and other receivables 213 284
Total assets 40,006,269 36,221,998
Due to broker for securities purchased and other payables 4,516 2,796
Collateral held under securities lending agreements 200,064 693,505
Total liabilities 204,580 696,301
Net assets available for benefits 39,801,689 35,525,697
Net appreciation in value of investments 5,867,005  
Interest 95,113  
Dividends 65,793  
Other income 2,255  
Investment manager fees (3,597)  
Total investment income 6,026,569  
Master Trust Balances | Cash equivalents and short-term investment fund    
EBP, Master Trust [Line Items]    
Investment, fair value 78,177 93,059
Master Trust Balances | U.S. equities    
EBP, Master Trust [Line Items]    
Investment, fair value 4,048,009 3,594,037
Master Trust Balances | Common/collective trust funds    
EBP, Master Trust [Line Items]    
Investment, fair value 32,627,651 28,679,632
Master Trust Balances | Collateral held under securities lending agreements    
EBP, Master Trust [Line Items]    
Investment, fair value 200,064 693,505
Master Trust Balances | Synthetic guaranteed investment contracts    
EBP, Master Trust [Line Items]    
Investment, contract value 3,052,155 3,161,481
Plan's Interest in Master Trust Balances    
EBP, Master Trust [Line Items]    
Investment, fair value 36,499,000 32,615,755
Investment, contract value 3,005,171 3,112,812
Dividends, interest, taxes and other receivables 210 281
Total assets 39,504,381 35,728,848
Due to broker for securities purchased and other payables 4,449 2,746
Collateral held under securities lending agreements 197,935 685,586
Total liabilities 202,384 688,332
Net assets available for benefits 39,301,997 35,040,516
Plan's Interest in Master Trust Balances | Cash equivalents and short-term investment fund    
EBP, Master Trust [Line Items]    
Investment, fair value 77,001 91,680
Plan's Interest in Master Trust Balances | U.S. equities    
EBP, Master Trust [Line Items]    
Investment, fair value 4,030,621 3,576,126
Plan's Interest in Master Trust Balances | Common/collective trust funds    
EBP, Master Trust [Line Items]    
Investment, fair value 32,193,443 28,262,363
Plan's Interest in Master Trust Balances | Collateral held under securities lending agreements    
EBP, Master Trust [Line Items]    
Investment, fair value 197,935 685,586
Plan's Interest in Master Trust Balances | Synthetic guaranteed investment contracts    
EBP, Master Trust [Line Items]    
Investment, contract value $ 3,005,171 $ 3,112,812