Risk Management Activities and Derivative Transactions Risk Management Activities and Derivative Transactions - Mark-to-Market Values of TVA Derivatives (Details) (USD $)
In Millions, unless otherwise specified

200 million Sterling currency swap | Other long-term liabilities

250 million Sterling currency swap | Other long-term assets

150 million Sterling currency swap | Other long-term assets

150 million Sterling currency swap | Other long-term liabilities

$1.0 billion notional interest rate swap | Other long-term liabilities

$476 million notional interest rate swap | Other long-term liabilities

$42 million notional interest rate swap | Other long-term liabilities

Commodity contract derivatives

Commodity contract derivatives | Other long-term assets

Commodity contract derivatives | Other current assets

Commodity contract derivatives | Other long-term liabilities

Commodity contract derivatives | Accounts payable and accrued liabilities

Margin cash account | Other current assets

Derivatives Under FTP

Derivatives Under FTP | Other long-term assets

Derivatives Under FTP | Other current assets

Derivatives Under FTP | Other long-term liabilities

Derivatives Under FTP | Accounts payable and accrued liabilities