Borrowed Funds (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total borrowed funds	$ 30,784	$ 37,195
PNC Capital Trust C
Debt Instrument [Line Items]
Carrrying value - junior subordinated debt	205
Trust preferred securities	$ 200
PNC Capital Trust C \| 3-month LIBOR
Debt Instrument [Line Items]
Basis spread on LIBOR rate - trust preferred securities	0.57%
Parent Company
Debt Instrument [Line Items]
Total borrowed funds	$ 11,351	10,583
Bank
Debt Instrument [Line Items]
Total borrowed funds	16,306	23,591
Senior Notes \| Parent Company
Debt Instrument [Line Items]
Total borrowed funds	10,369	9,573
Basis adjustments - fair value accounting hedges	252
Senior Notes \| Bank
Debt Instrument [Line Items]
Total borrowed funds	10,292	14,698
Basis adjustments - fair value accounting hedges	190
Subordinated Debt \| Parent Company
Debt Instrument [Line Items]
Total borrowed funds	777	805
Basis adjustments - fair value accounting hedges	28
Subordinated Debt \| Bank
Debt Instrument [Line Items]
Total borrowed funds	6,014	$ 5,393
Basis adjustments - fair value accounting hedges	$ 193

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- Definition

In order to issue trust preferred securities, a sponsor forms a trust by investing a nominal amount of cash to purchase all of the voting common stock of the trust. The trust issues nonvoting, mandatorily redeemable preferred securities to outside investors in exchange for cash. The proceeds received from the issuance of the preferred securities, together with the cash received for issuing the common stock to the sponsor, is then loaned to the sponsor in exchange for a note which has the same terms as the trust preferred securities. Trust preferred securities possesses characteristics of both equity and debt issues and are generally issued by bank holding companies.

+ References

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- 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
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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

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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.

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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