Borrowed Funds (FHLB Borrowings, Senior Debt and Subordinated Debt) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Borrowed funds	$ 42,110	$ 60,263
Total FHLB, Senior and Sub Debt	38,804	51,485
Parent Company [Member]
Debt Instrument [Line Items]
Borrowed funds	10,690	9,825
Parent Company [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Borrowed funds	$ 9,674	8,843
Parent Company [Member] \| Senior Notes [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Interest rate	2.20%
Parent Company [Member] \| Senior Notes [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Interest rate	3.50%
Parent Company [Member] \| Subordinated Debt [Member]
Debt Instrument [Line Items]
Interest rate	3.90%
Borrowed funds	$ 811	777
Parent Company [Member] \| Junior Subordinated Debt [Member]
Debt Instrument [Line Items]
Interest rate	0.82%
Borrowed funds	$ 205	205
Subsidiaries [Member]
Debt Instrument [Line Items]
Borrowed funds	28,114	41,660
Subsidiaries [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Borrowed funds	$ 17,165	20,167
Subsidiaries [Member] \| Senior Notes [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Interest rate	0.00%
Subsidiaries [Member] \| Senior Notes [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Interest rate	3.50%
Subsidiaries [Member] \| Subordinated Debt [Member]
Debt Instrument [Line Items]
Borrowed funds	$ 5,449	5,152
Subsidiaries [Member] \| Subordinated Debt [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Interest rate	2.70%
Subsidiaries [Member] \| Subordinated Debt [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Interest rate	4.20%
Subsidiaries [Member] \| Federal Home Loan Bank Borrowings [Member]
Debt Instrument [Line Items]
Borrowed funds	$ 5,500	$ 16,341
Subsidiaries [Member] \| Federal Home Loan Bank Borrowings [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Interest rate	0.34%
Subsidiaries [Member] \| Federal Home Loan Bank Borrowings [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Interest rate	0.57%

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations excluding other borrowings.

No definition available.

+ Details

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

- Definition

Amount of short-term and long-term debt and lease obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13,16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

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Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- 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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