Derivatives and Hedging Activities - Credit Risk Contingent Feature (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Credit Derivatives [Line Items]
Additional collateral aggregate fair value	$ 2
One rating downgrade | Moody’s
Credit Derivatives [Line Items]
Additional collateral aggregate fair value	3	$ 1
One rating downgrade | S&P
Credit Derivatives [Line Items]
Additional collateral aggregate fair value	3	1
Two rating downgrades | Moody’s
Credit Derivatives [Line Items]
Additional collateral aggregate fair value	3	1
Two rating downgrades | S&P
Credit Derivatives [Line Items]
Additional collateral aggregate fair value	3	1
Three rating downgrades | Moody’s
Credit Derivatives [Line Items]
Additional collateral aggregate fair value	3	1
Three rating downgrades | S&P
Credit Derivatives [Line Items]
Additional collateral aggregate fair value	$ 3	$ 1