Total Equity and Other Comprehensive Income (Other Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Net Unrealized Gains Losses on Non Otti Securities [Abstract]
Increase in net unrealized gains(losses) on non-OTTI securities	$ 68	$ (14)	$ 304	$ 791
Less: Net gains (losses) realized as a yield adjustment reclassified to investment securities in interest income, before tax	10	5	20	19
Less: Net gains (losses) realized on sales of non-OTTI securities reclassified to noninterest income, before tax	(3)	6	3	20
Net unrealized gains (losses) on non-OTTI securities	61	(25)	281	752
Other Comprehensive Income (Loss), Non Otti Securities Adjustment, Tax	(20)	10	(103)	(275)
Net unrealized gains (losses) on non-OTTI securities, Activity, After Tax	41	(15)	178	477
Net Unrealized Gains Losses On Otti Securities [Abstract]
Increase in net unrealized gains (losses) on OTTI securities, Pretax	66	38	165	16
Less: Net gains (losses) realized on sales of OTTI securities reclassified to noninterest income, before tax			2
Less: Net OTTI losses realized in net income, Pre-tax			(1)	(1)
Net unrealized gains (losses) on OTTI securities	66	38	164	17
Net unrealized gains (losses) on OTTI securities, tax	(22)	(14)	(60)	(6)
Net unrealized gains (losses) on OTTI securities, Activity, After Tax	44	24	104	11
Net unrealized gains (losses) on cash flow hedge derivatives [Abstract]
Increase in net unrealized gains (losses) on cash flow hedge derivatives, Pretax	(2)	(63)	15	328
Less: Net gains (losses) realized as a yield adjustment reclassified to loan interest income, Before Tax	38	51	128	167
Less: Net gains (losses) realized as a yield adjustment reclassified to investment securities interest income, Before Tax	5	10	16	23
Less: Net gains (losses) realized on sales of securities reclassified to noninterest income, Before Tax	2	1	5
Net unrealized gains (losses) on cash flow hedge derivatives, Before Tax	(47)	(125)	(134)	138
Net unrealized gains (losses) on cash flow hedge derivatives, tax	17	45	49	(51)
Net unrealized gains (losses) on cash flow hedge derivatives, Net of tax, Total	(30)	(80)	(85)	87
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Tax, [Abstract]
Net pension and other postretirement benefit plan activity, Before tax			(38)	(5)
Amortization of actuarial loss (gain) reclassified to other noninterest expense, Before tax	12	13	36	37
Amortization of prior service cost (credit) reclassified to other noninterest expense, Before tax	(1)	(2)	(4)	(6)
Pension and other postretirement benefit plan adjustments, net activity, Pre-Tax	11	11	(6)	26
Pension and other postretirement benefit plan adjustments, net activity, Tax	(4)	(5)	2	(10)
Pension and other postretirement benefit plan adjustments, net activity, After Tax	7	6	(4)	16
Other Comprehensive Income Other Adjustments [Abstract]
PNC's portion of BlackRock's OCI, Before tax	4	(28)	26	(40)
Net investment hedge derivatives, Before tax	(26)	27	(76)	136
Foreign Currency Transaction and Translation Adjustment, before Tax	28	(24)	82	(136)
Total Other, net activity, Before tax	6	(25)	32	(40)
Total Other, net activity, Tax	8		18	(35)
Total Other, net activity, After tax	14	(25)	50	(75)
Other Comprehensive Income Loss Before Tax	97	(126)	337	893
Other Comprehensive Income (Loss), Tax	(21)	36	(94)	(377)
Other Comprehensive Income (Loss), Net of Tax	$ 76	$ (90)	$ 243	$ 516