Securities (Amortized Cost, Gross Unrealized Gains, Gross Unrealized Losses and Approximate Fair Values of AFS Securities) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
AFS securities, amortized cost	$ 20,660	$ 22,168
AFS securities, gross unrealized gains	603	574
AFS securities, gross unrealized losses	356	638
AFS securities, fair value	20,907us-gaap_AvailableForSaleSecurities	22,104us-gaap_AvailableForSaleSecurities
U.S. Treasury [Member]
AFS securities, amortized cost	1,230	595
AFS securities, gross unrealized gains	1	0
AFS securities, gross unrealized losses	0	0
AFS securities, fair value	1,231	595
MBS Issued by GSE [Member]
AFS securities, amortized cost	16,358	18,397
AFS securities, gross unrealized gains	93	78
AFS securities, gross unrealized losses	297	546
AFS securities, fair value	16,154	17,929
States and Political Subdivisions [Member]
AFS securities, amortized cost	1,913	1,877
AFS securities, gross unrealized gains	120	65
AFS securities, gross unrealized losses	59	91
AFS securities, fair value	1,974	1,851
Non-Agency MBS [Member]
AFS securities, amortized cost	232	264
AFS securities, gross unrealized gains	32	27
AFS securities, gross unrealized losses	0	0
AFS securities, fair value	264	291
Other [Member]
AFS securities, amortized cost	41	46
AFS securities, gross unrealized gains	0	0
AFS securities, gross unrealized losses	0	1
AFS securities, fair value	41	45
Securities Acquired from FDIC [Member]
AFS securities, amortized cost	886	989
AFS securities, gross unrealized gains	357	404
AFS securities, gross unrealized losses	0	0
AFS securities, fair value	$ 1,243	$ 1,393

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562

+ Details

Name:	us-gaap_AvailableForSaleSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesAmortizedCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	bbt_InvestmentsAxis=bbt_OtherSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	bbt_InvestmentsAxis=bbt_SecuritiesAcquiredFromFdicMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	bbt_InvestmentsAxis=us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	bbt_InvestmentsAxis=us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	bbt_InvestmentsAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	bbt_InvestmentsAxis=us-gaap_USTreasurySecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: