Loan Sale and Servicing Activities and Variable Interest Entities (Non-Consolidated VIEs) (Details) - Variable Interest Entity, Primary Beneficiary [Member] - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
PNC Risk of Loss	$ 16,907	$ 12,807
Carrying Value of Assets Owned by PNC	16,895	12,739
Carrying Value of Liabilities Owned by PNC	790	858
Mortgage-Backed Securitizations [Member]
PNC Risk of Loss	13,892	9,738
Carrying Value of Assets Owned by PNC	13,892	9,738
Tax Credit Investments And Other [Member]
PNC Risk of Loss	3,015	3,069
Carrying Value of Assets Owned by PNC	3,003	3,001
Carrying Value of Liabilities Owned by PNC	$ 790	$ 858

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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=77990344&loc=d3e5728-111685

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=77990344&loc=d3e5747-111685

+ Details

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- 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

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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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- Details

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