Long-Term Debt - Schedule of Long Term Debt, Interest Rates and Maturity Dates (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Debt Instruments [Line Items]
Long-term Debt, Carrying Amount	$ 23,236	$ 23,648
Other long-term debt
Debt Instruments [Line Items]
Long-term Debt, Carrying Amount	$ 135	205
BB&T Corporation \| Senior notes \| Fixed rate
Debt Instruments [Line Items]
Maturity Date Range, Start	Jan. 01, 2019
Maturity Date Range, End	Dec. 31, 2025
Effective Rate	3.58%
Long-term Debt, Carrying Amount	$ 9,340	8,562
BB&T Corporation \| Senior notes \| Fixed rate \| Min
Debt Instruments [Line Items]
Stated Rate	2.05%
BB&T Corporation \| Senior notes \| Fixed rate \| Max
Debt Instruments [Line Items]
Stated Rate	6.85%
BB&T Corporation \| Senior notes \| Floating rate
Debt Instruments [Line Items]
Maturity Date Range, Start	Jan. 01, 2019
Maturity Date Range, End	Dec. 31, 2022
Effective Rate	2.93%
Long-term Debt, Carrying Amount	$ 2,397	2,547
BB&T Corporation \| Senior notes \| Floating rate \| Min
Debt Instruments [Line Items]
Stated Rate	2.56%
BB&T Corporation \| Senior notes \| Floating rate \| Max
Debt Instruments [Line Items]
Stated Rate	3.05%
BB&T Corporation \| Subordinated notes \| Fixed rate
Debt Instruments [Line Items]
Maturity Date Range, Start	Jan. 01, 2019
Maturity Date Range, End	Dec. 31, 2022
Effective Rate	2.69%
Long-term Debt, Carrying Amount	$ 903	933
BB&T Corporation \| Subordinated notes \| Fixed rate \| Min
Debt Instruments [Line Items]
Stated Rate	3.95%
BB&T Corporation \| Subordinated notes \| Fixed rate \| Max
Debt Instruments [Line Items]
Stated Rate	5.25%
Branch Bank \| Senior notes \| Fixed rate
Debt Instruments [Line Items]
Maturity Date Range, Start	Jan. 01, 2019
Maturity Date Range, End	Dec. 31, 2022
Effective Rate	3.32%
Long-term Debt, Carrying Amount	$ 4,859	5,653
Branch Bank \| Senior notes \| Fixed rate \| Min
Debt Instruments [Line Items]
Stated Rate	1.45%
Branch Bank \| Senior notes \| Fixed rate \| Max
Debt Instruments [Line Items]
Stated Rate	2.85%
Branch Bank \| Senior notes \| Floating rate
Debt Instruments [Line Items]
Maturity Date Range, Start	Jan. 01, 2019
Maturity Date Range, End	Dec. 31, 2020
Effective Rate	2.81%
Long-term Debt, Carrying Amount	$ 1,149	1,149
Branch Bank \| Senior notes \| Floating rate \| Min
Debt Instruments [Line Items]
Stated Rate	2.54%
Branch Bank \| Senior notes \| Floating rate \| Max
Debt Instruments [Line Items]
Stated Rate	2.87%
Branch Bank \| Subordinated notes \| Fixed rate
Debt Instruments [Line Items]
Maturity Date Range, Start	Jan. 01, 2025
Maturity Date Range, End	Dec. 31, 2026
Effective Rate	4.35%
Long-term Debt, Carrying Amount	$ 2,016	2,119
Branch Bank \| Subordinated notes \| Fixed rate \| Min
Debt Instruments [Line Items]
Stated Rate	3.63%
Branch Bank \| Subordinated notes \| Fixed rate \| Max
Debt Instruments [Line Items]
Stated Rate	3.80%
Branch Bank \| FHLB advances
Debt Instruments [Line Items]
Maturity Date Range, Start	Jan. 01, 2018
Maturity Date Range, End	Dec. 31, 2034
Effective Rate	2.54%
Long-term Debt, Carrying Amount	$ 2,437	$ 2,480
Weighted average maturity of FHLB advances	3 years 1 month 6 days
Branch Bank \| FHLB advances \| Min
Debt Instruments [Line Items]
Stated Rate	0.00%
Branch Bank \| FHLB advances \| Max
Debt Instruments [Line Items]
Stated Rate	5.50%

Line items represent the type of debt that has been swapped

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Weighted average maturity of FHLB advances

+ References

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- Definition

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

+ References

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-Name Accounting Standards Codification
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Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

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.

+ References

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