Income Taxes (IRS Tax Examination Status) (Details) - Internal Revenue Service (IRS)	12 Months Ended
Dec. 31, 2017
Completed
Income Tax Examination Earliest Year Under Examination	2014
Income Tax Examination Latest Year Under Examination	2015
Under Exam
Income Tax Examination, Year under Examination	2016

Earliest tax year being audited in the income tax examination, in CCYY format.

No definition available.

Name:	pnc_IncomeTaxExaminationEarliestYearUnderExamination
Namespace Prefix:	pnc_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	duration