Derivative Financial Instruments - Dealer Counterparties and Central Clearing Parties (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Credit Derivatives [Line Items]
Cash collateral received from dealer counterparties		$ 53
Cash collateral posted		82
Dealer Counterparties
Credit Derivatives [Line Items]
Cash collateral received from dealer counterparties	$ 186	56
Derivatives in a net gain position secured by collateral received	184	55
Unsecured positions in a net gain with dealer counterparties after collateral postings	1	2
Cash collateral posted	75	75
Derivatives in a net loss position	74	76
Additional collateral that would have been posted had BB&T's credit ratings dropped below investment grade	0	1
Central Clearing Parties
Credit Derivatives [Line Items]
Cash collateral posted	17	17
Derivatives in a net loss position	15	8
Securities pledged to central clearing parties	$ 155	$ 124