Loan Sale and Servicing Activities and Variable Interest Entities (Non-Consolidated VIEs) (Details) - Variable Interest Entity, Primary Beneficiary [Member] - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
PNC Risk of Loss	$ 24,114	$ 22,418
Carrying Value of Assets Owned by PNC	23,995	22,315
Carrying Value of Liabilities Owned by PNC	921	1,101
Mortgage-Backed Securitizations [Member]
PNC Risk of Loss	21,109	19,287
Carrying Value of Assets Owned by PNC	21,109	19,287
Carrying Value of Liabilities Owned by PNC	1
Tax Credit Investments And Other [Member]
PNC Risk of Loss	3,005	3,131
Carrying Value of Assets Owned by PNC	2,886	3,028
Carrying Value of Liabilities Owned by PNC	$ 920	$ 1,101

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118582676&loc=d3e5747-111685

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=118582676&loc=d3e5728-111685

+ Details

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Period Type:	instant

- Definition

Carrying amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph a
-URI http://asc.fasb.org/extlink&oid=118582676&loc=d3e5728-111685

+ Details

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- Definition

Carrying amount of the liabilities in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

+ References

+ Details

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- Details

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Namespace Prefix:
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- Details

Name:	us-gaap_FinancialInstrumentAxis=pnc_MortgageBackedSecuritizationsMember
Namespace Prefix:
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- Details

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