Total Equity and Other Comprehensive Income (Other Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Net Unrealized Gains Losses on Non Otti Securities [Abstract]
Increase in net unrealized gains (losses) on non-OTTI securities	$ (161)	$ 169	$ (806)	$ 236
Less: Net gains (losses) realized as a yield adjustment reclassified to investment securities in interest income, before tax	2	5	6	10
Less: Net gains (losses) realized on sales of non-OTTI securities reclassified to noninterest income, before tax	(8)	13	(11)	6
Net increase (decrease), pre-tax	(155)	151	(801)	220
Effect of income taxes	36	(58)	186	(83)
Net increase (decrease), after-tax	(119)	93	(615)	137
Net Unrealized Gains Losses On Otti Securities [Abstract]
Increase in net unrealized gains (losses) on OTTI securities, Pretax	3	61	17	98
Less: OTTI losses realized on securities reclassified to noninterest income		(1)		(1)
Less: Net gains (losses) realized on sales of securities reclassified to noninterest income				2
Net increase (decrease), pre-tax	3	62	17	97
Effect of income taxes	(1)	(24)	(5)	(37)
Net increase (decrease), after-tax	2	38	12	60
Net unrealized gains (losses) on cash flow hedge derivatives [Abstract]
Increase in net unrealized gains (losses) on cash flow hedge derivatives, Pretax	(94)	39	(255)	17
Less: Net gains (losses) realized as a yield adjustment reclassified to loan interest income, Before Tax	11	44	37	90
Less: Net gains (losses) realized as a yield adjustment reclassified to investment securities interest income, Before Tax	3	5	7	11
Less: Net gains (losses) realized on sales of securities reclassified to noninterest income	5		7	3
Net increase (decrease), pre-tax	(113)	(10)	(306)	(87)
Effect of income taxes	26	4	70	32
Net increase (decrease), after-tax	(87)	(6)	(236)	(55)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax [Abstract]
Net pension and other postretirement benefit plan activity, Before tax	5	36	66	(38)
Amortization of actuarial loss (gain) reclassified to other noninterest expense, Before tax	1	11	2	24
Amortization of prior service cost (credit) reclassified to other noninterest expense, Before tax		(2)	1	(3)
Net increase (decrease), pre-tax	6	45	69	(17)
Effect of income taxes	(1)	(17)	(16)	6
Net increase (decrease), after-tax	5	28	53	(11)
Other Comprehensive Income Other Adjustments [Abstract]
PNC’s portion of BlackRock’s OCI	(37)	20	(15)	22
Net investment hedge derivatives	69	(36)	30	(50)
Foreign currency translation adjustments and other	(67)	38	(23)	54
Net increase (decrease), pre-tax	(35)	22	(8)	26
Effect of income taxes	(7)	6	(4)	10
Net increase (decrease), after-tax	(42)	28	(12)	36
Other comprehensive income (loss), before tax and net of reclassifications into Net income	(294)	270	(1,029)	239
Other Comprehensive Income (Loss), Tax	53	(89)	231	(72)
Other comprehensive income (loss), after tax and net of reclassifications into Net income	$ (241)	$ 181	$ (798)	$ 167