Commitments (Narrative) (Details) - Standby letters of credit [Member] $ in Billions	Sep. 30, 2020 USD ($)
Loss Contingencies [Line Items]
Internal credit ratings (as a percentage of portfolio) - Pass	96.00%
Standby letters of credit - Assets securing certain specifically identified standby letters of credit	$ 1.1
Standby letters of credit and participations in standby letters of credit - Liability carrying amount	$ 0.2

Amount of any assets held either as collateral or by third parties that, upon the occurrence of any triggering event or condition under the guarantee, the guarantor can obtain and liquidate to recover all or a portion of the amounts paid under the guarantee.

No definition available.

+ Details

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Namespace Prefix:	pnc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of standby letters of credit (including risk participations in standby letters of credit and bankers' acceptances issued by other financial institutions) with an internal credit rating of pass, indicating the expected risk of loss is currently low.

+ References

No definition available.

+ Details

Name:	pnc_StandbyLettersOfCreditPass
Namespace Prefix:	pnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12069-110248

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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Namespace Prefix:
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Balance Type:
Period Type: