Derivative Financial Instruments - Dealer Counterparties and Central Clearing Parties (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Credit Derivatives [Line Items]
Cash collateral received from dealer counterparties	$ 53	$ 20
Cash collateral posted	82	344
Dealer Counterparties
Credit Derivatives [Line Items]
Cash collateral received from dealer counterparties	56	21
Derivatives in a net gain position secured by that collateral	55	22
Unsecured positions in a net gain with dealer counterparties after collateral postings	2	2
Cash collateral posted	75	172
Derivatives in a net loss position	76	171
Additional collateral that would have been posted had BB&T's credit ratings dropped below investment grade	1	0
Central Clearing Parties
Credit Derivatives [Line Items]
Cash collateral posted	17	177
Derivatives in a net loss position	8	176
Securities pledged to central clearing parties	$ 124	$ 91