Long-Term Debt - Schedule of Long Term Debt, Interest Rates and Maturity Dates (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Debt Instruments [Line Items]
Long-term Debt, Carrying Amount	$ 41,339	$ 23,709
FHLB advances
Debt Instruments [Line Items]
Weighted average maturity of FHLB advances	1 year 9 months 18 days
Truist Financial Corporation
Debt Instruments [Line Items]
Long-term Debt, Carrying Amount	$ 18,130	13,709
Truist Financial Corporation \| Senior notes \| Fixed rate
Debt Instruments [Line Items]
Maturity Date Range, Start	Jan. 01, 2020
Maturity Date Range, End	Dec. 31, 2028
Effective Rate	2.25%
Long-term Debt, Carrying Amount	$ 14,431	10,408
Truist Financial Corporation \| Senior notes \| Fixed rate \| Min
Debt Instruments [Line Items]
Stated Rate	2.05%
Truist Financial Corporation \| Senior notes \| Fixed rate \| Max
Debt Instruments [Line Items]
Stated Rate	6.00%
Truist Financial Corporation \| Senior notes \| Floating rate
Debt Instruments [Line Items]
Maturity Date Range, Start	Jan. 01, 2020
Maturity Date Range, End	Dec. 31, 2022
Effective Rate	2.65%
Long-term Debt, Carrying Amount	$ 1,749	2,398
Truist Financial Corporation \| Senior notes \| Floating rate \| Min
Debt Instruments [Line Items]
Stated Rate	2.13%
Truist Financial Corporation \| Senior notes \| Floating rate \| Max
Debt Instruments [Line Items]
Stated Rate	2.75%
Truist Financial Corporation \| Subordinated notes \| Fixed rate
Debt Instruments [Line Items]
Maturity Date Range, Start	Jan. 01, 2022
Maturity Date Range, End	Dec. 31, 2029
Effective Rate	3.11%
Long-term Debt, Carrying Amount	$ 1,227	903
Truist Financial Corporation \| Subordinated notes \| Fixed rate \| Min
Debt Instruments [Line Items]
Stated Rate	3.88%
Truist Financial Corporation \| Subordinated notes \| Fixed rate \| Max
Debt Instruments [Line Items]
Stated Rate	6.00%
Truist Financial Corporation \| Capital Note
Debt Instruments [Line Items]
Maturity Date Range, Start	Jan. 01, 2027
Maturity Date Range, End	Dec. 31, 2028
Effective Rate	3.61%
Long-term Debt, Carrying Amount	$ 611	0
Truist Financial Corporation \| Capital Note \| Min
Debt Instruments [Line Items]
Stated Rate	2.54%
Truist Financial Corporation \| Capital Note \| Max
Debt Instruments [Line Items]
Stated Rate	3.08%
Truist Financial Corporation \| Structured Finance
Debt Instruments [Line Items]
Maturity Date Range, Start	Jan. 31, 2021
Maturity Date Range, End	Dec. 31, 2026
Long-term Debt, Carrying Amount	$ 112	0
Truist Bank \| Other long-term debt
Debt Instruments [Line Items]
Long-term Debt, Carrying Amount	$ 1,133	132
Truist Bank \| Senior notes \| Fixed rate
Debt Instruments [Line Items]
Maturity Date Range, Start	Jan. 01, 2020
Maturity Date Range, End	Dec. 31, 2037
Effective Rate	2.36%
Long-term Debt, Carrying Amount	$ 11,560	4,895
Truist Bank \| Senior notes \| Fixed rate \| Min
Debt Instruments [Line Items]
Stated Rate	2.13%
Truist Bank \| Senior notes \| Fixed rate \| Max
Debt Instruments [Line Items]
Stated Rate	4.05%
Truist Bank \| Senior notes \| Floating rate
Debt Instruments [Line Items]
Maturity Date Range, Start	Jan. 01, 2020
Maturity Date Range, End	Dec. 31, 2022
Effective Rate	2.31%
Long-term Debt, Carrying Amount	$ 1,554	1,149
Truist Bank \| Senior notes \| Floating rate \| Min
Debt Instruments [Line Items]
Stated Rate	2.13%
Truist Bank \| Senior notes \| Floating rate \| Max
Debt Instruments [Line Items]
Stated Rate	2.49%
Truist Bank \| Subordinated notes \| Fixed rate
Debt Instruments [Line Items]
Maturity Date Range, Start	Jan. 01, 2020
Maturity Date Range, End	Dec. 31, 2029
Effective Rate	2.89%
Long-term Debt, Carrying Amount	$ 3,872	2,075
Truist Bank \| Subordinated notes \| Fixed rate \| Min
Debt Instruments [Line Items]
Stated Rate	2.64%
Truist Bank \| Subordinated notes \| Fixed rate \| Max
Debt Instruments [Line Items]
Stated Rate	5.40%
Truist Bank \| FHLB advances
Debt Instruments [Line Items]
Maturity Date Range, Start	Jan. 01, 2020
Maturity Date Range, End	Dec. 31, 2034
Effective Rate	2.08%
Long-term Debt, Carrying Amount	$ 4,141	1,749
Truist Bank \| FHLB advances \| Min
Debt Instruments [Line Items]
Stated Rate	0.00%
Truist Bank \| FHLB advances \| Max
Debt Instruments [Line Items]
Stated Rate	5.36%
Nonbank \| Other long-term debt
Debt Instruments [Line Items]
Long-term Debt, Carrying Amount	$ 949	$ 0

Line items represent the type of debt that has been swapped

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Latest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

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Earliest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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