XML 124 R83.htm IDEA: XBRL DOCUMENT v3.10.0.1
Risk Management Activities and Derivative Transactions Risk Management Activities and Derivative Transactions - Currency Swaps Outstanding (Details)
£ in Millions
 12 Months Ended
Sep. 30, 2018
GBP (£)
Bond_issues
Derivative  
Number of British pound sterling denominated bond transactions | Bond_issues 3
1999 Currency Swap Contract  
Derivative  
Effective Date of Currency Swap Contract 1999
Associated TVA bond issues currency exposure £ 200
Expiration Date of Swap 2021
Overall effective cost to TVA 5.81%
2001 Currency Swap Contract  
Derivative  
Effective Date of Currency Swap Contract 2001
Associated TVA bond issues currency exposure £ 250
Expiration Date of Swap 2032
Overall effective cost to TVA 6.59%
2003 Currency Swap Contract  
Derivative  
Effective Date of Currency Swap Contract 2003
Associated TVA bond issues currency exposure £ 150
Expiration Date of Swap 2043
Overall effective cost to TVA 4.96%