Long-Term Debt - Schedule of Long Term Debt, Interest Rates and Maturity Dates (Details) - USD ($) $ in Millions		Sep. 30, 2020	Dec. 31, 2019
Debt Instruments [Line Items]
Long-term Debt, Carrying Amount		$ 41,008	$ 41,339
Truist Financial Corporation | Senior notes | Fixed rate
Debt Instruments [Line Items]
Long-term Debt, Carrying Amount		16,029	14,431
Truist Financial Corporation | Senior notes | Floating rate
Debt Instruments [Line Items]
Long-term Debt, Carrying Amount		900	1,749
Truist Financial Corporation | Subordinated notes | Fixed rate
Debt Instruments [Line Items]
Long-term Debt, Carrying Amount		1,288	1,227
Truist Financial Corporation | Capital Notes
Debt Instruments [Line Items]
Long-term Debt, Carrying Amount		614	611
Truist Financial Corporation | Structured Notes
Debt Instruments [Line Items]
Long-term Debt, Carrying Amount	[1]	109	112
Truist Bank | Senior notes | Fixed rate
Debt Instruments [Line Items]
Long-term Debt, Carrying Amount		12,544	11,560
Truist Bank | Senior notes | Floating rate
Debt Instruments [Line Items]
Long-term Debt, Carrying Amount		1,751	1,554
Truist Bank | Subordinated notes | Fixed rate
Debt Instruments [Line Items]
Long-term Debt, Carrying Amount		5,156	3,872
Truist Bank | FHLB advances
Debt Instruments [Line Items]
Long-term Debt, Carrying Amount		881	4,141
Truist Bank | Other long-term debt
Debt Instruments [Line Items]
Long-term Debt, Carrying Amount	[2]	1,091	1,133
Nonbank | Other long-term debt
Debt Instruments [Line Items]
Long-term Debt, Carrying Amount	[3]	$ 645	$ 949

[1] (1) Consist of notes with various terms that include fixed or floating rate interest, or returns that are linked to an equity index.

[2] (2) Includes finance leases, tax credit investments, and other.

[3] (3) Includes debt associated with structured real estate leases.