Derivative Financial Instruments - Dealer Counterparties and Central Clearing Parties (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Credit Derivatives [Line Items]
Cash collateral received from dealer counterparties	$ 39	$ 20
Cash collateral posted	162	344
Dealer Counterparties [Member]
Credit Derivatives [Line Items]
Cash collateral received from dealer counterparties	40	21
Derivatives in a net gain position secured by that collateral	41	22
Unsecured positions in a net gain with dealer counterparties after collateral postings	2	2
Cash collateral posted	163	172
Derivatives in a net loss position	166	171
Additional collateral that would have been posted had BB&T's credit ratings dropped below investment grade	4	0
Central Clearing Parties [Member]
Credit Derivatives [Line Items]
Cash collateral posted	14	177
Derivatives in a net loss position	2	176
Securities pledged to central clearing parties	$ 75	$ 91