Derivative Financial Instruments - Cash Flow and Fair Value Hedges (Details) - USD ($) $ in Millions	6 Months Ended		12 Months Ended
	Jun. 30, 2022		Dec. 31, 2021
Derivative [Line Items]
Max time period which Truist is hedging a portion of the var. in future cash flows for forecasted transactions excluding those transactions relating to the payment of var. int. on existing instruments	7 years
Debt Securities, Held-to-maturity, Derivative, Cumulative Gain (Loss)	$ 485
Cash flow hedges
Derivative [Line Items]
Net unrecognized after-tax gain (loss) on active hedges recorded in AOCI	(44)		$ 0
Net unrecognized after-tax gain (loss) on terminated hedges recorded in AOCI (to be recognized in earnings through 2022)	(1)		(9)
Estimated portion of net after-tax gain (loss) on terminated hedges to be reclassified from AOCI into earnings during the next 12 months	(3)		(9)
Fair Value Hedges
Derivative [Line Items]
Unrecognized pre-tax net gain (loss) on terminated hedges (to be recognized as interest primarily through 2030) (1)	756	[1]	767
Portion of pre-tax net gain (loss) on terminated hedges to be recognized as a change in interest during the next 12 months	$ 179		$ 231

[1] Includes deferred gains that are recorded in AOCI as a result of the reclassification to HTM of previously hedged securities of $485 million at June 30, 2022.