Accounting Policies (Details) $ in Millions		12 Months Ended
		Dec. 31, 2018 USD ($) office	Dec. 31, 2016 USD ($)	Jan. 01, 2019 USD ($)	Dec. 31, 2017 USD ($)
Number of international offices | office		4
Charge off threshold - small business commercial loans		$ 1
Cumulative Effect on Retained Earnings, Net of Tax	[1]				$ (16)
Minimum | Furniture and Equipment
Estimated useful life of property and equipment		1 year
Minimum | Software and Software Development Costs
Estimated useful life of property and equipment		1 year
Maximum | Furniture and Equipment
Estimated useful life of property and equipment		10 years
Maximum | Buildings
Estimated useful life of property and equipment		40 years
Maximum | Leasehold Improvements
Estimated useful life of property and equipment		15 years
Maximum | Software and Software Development Costs
Estimated useful life of property and equipment		10 years
PNC Foundation | Stock
Contribution of stock			$ 200
Accounting Standards Update 2016-02 [Member] | Subsequent Event
Lease liabilities				$ 2,100
Right-of-use assets				2,000
Retained Earnings
Cumulative Effect on Retained Earnings, Net of Tax	[1]				$ (22)
Retained Earnings | Accounting Standards Update 2016-02 [Member] | Subsequent Event
Cumulative Effect on Retained Earnings, Net of Tax				$ 83

[1] Represents the cumulative effect of adopting ASU 2014-09, ASU 2016-01, ASU 2017-12 and ASU 2018-02. See Recently Adopted Accounting Standards portion of Note 1 Accounting Policies for additional detail on the adoption of these ASUs.