Derivative Financial Instruments - Schedule of Derivative Instruments Summary of Collateral Positions with Counterparties (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Credit Derivatives [Line Items]
Cash collateral received from dealer counterparties	$ 20	$ 119
Cash collateral posted	344	450
Dealer Counterparties
Credit Derivatives [Line Items]
Cash collateral received from dealer counterparties	21	123
Derivatives in a net gain position secured by collateral received	22	123
Unsecured positions in a net gain with dealer counterparties after collateral postings	2	4
Cash collateral posted	172	138
Derivatives in a net loss position secured by collateral posted	171	144
Additional collateral that would have been posted had BB&T's credit ratings dropped below investment grade	0	8
Central Clearing Parties
Credit Derivatives [Line Items]
Cash collateral posted	177	313
Derivatives in a net loss position secured by collateral posted	176	318
Securities pledged to central clearing parties	$ 91	$ 119