Related Party (Summary of the Bancorp's Activities with its Principal Shareholders, Directors and Executives) (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Related Party Transactions
Outstanding balance on loans, net of participations and undrawn commitments	$ 49	$ 10
Commitments to Extend Credit
Related Party Transactions
Commitments to Extend Credit	75,696	70,415
Commitments to Extend Credit \| Due to related party
Related Party Transactions
Commitments to Extend Credit	741	706
Commitments to Extend Credit \| Director \| Due to related party
Related Party Transactions
Commitments to Extend Credit	736	700
Commitments to Extend Credit \| Executive Officer \| Due to related party
Related Party Transactions
Commitments to Extend Credit	$ 5	$ 6

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant