Financial Derivatives (Narrative) (Details) (USD $)	6 Months Ended	12 Months Ended
	Jun. 30, 2012	Dec. 31, 2011
Derivatives, Fair Value [Line Items]
Maximum length of time hedged in cash flow hedge, years	8
Fair value of written caps and floors liability	$ 4,000,000	$ 6,000,000
Cash and securities held under agreements that provide for exchanges of marketable securities or cash to collateralize either party's positions	1,100,000,000
Cash pledged under agreements that provide for exchanges of marketable securities or cash to collateralize either party's positions	1,000,000,000
Aggregate fair value of all derivative instruments with credit-risk-related contingent features	1,200,000,000
Collateral posted on derivative instruments with credit-risk-related contingent features	1,000,000,000
Maximum amount of collateral PNC would have been required to post if the credit-risk-related contingent features underlying these agreements had been triggered	200,000,000
Minimum term of Risk Participation Agreements, years	1
Maximum term of Risk Participation Agreements, years	25
Exposure from Risk Participation Agreements Based On The Fair Value Of The Underlying Swaps	154,000,000	145,000,000
Underlying Other Guarantor [Member] | Credit Default Swap [Member]
Derivatives, Fair Value [Line Items]
The maximum amount required to be paid related to sold credit default swap protection	0	94,000,000
Fair Value Hedging [Member] | Other Contract [Member]
Derivatives, Fair Value [Line Items]
The ineffective portion of the change in value of our fair value hedge derivatives	(25,000,000)	(22,000,000)
Forward Contracts [Member] | Cash Flow Hedging [Member]
Derivatives, Fair Value [Line Items]
Pretax portion	58,000,000
Aftertax portion	38,000,000
Scenario, Plan [Member] | Swap [Member] | Interest Rate Contracts [Member]
Derivatives, Fair Value [Line Items]
Pretax portion	265,000,000
Aftertax portion	$ 172,000,000