Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 1,356	$ 1,097	$ 2,595	$ 2,171
Other comprehensive income (loss), before tax and net of reclassifications into Net income:
Net unrealized gains (losses) on non-OTTI securities	(155)	151	(801)	220
Net unrealized gains (losses) on OTTI securities	3	62	17	97
Net unrealized gains (losses) on cash flow hedge derivatives	(113)	(10)	(306)	(87)
Pension and other postretirement benefit plan adjustments	6	45	69	(17)
Other	(35)	22	(8)	26
Other comprehensive income (loss), before tax and net of reclassifications into Net income	(294)	270	(1,029)	239
Income tax benefit (expense) related to items of other comprehensive income	53	(89)	231	(72)
Other comprehensive income (loss), after tax and net of reclassifications into Net income	(241)	181	(798)	167
Comprehensive income	1,115	1,278	1,797	2,338
Less: Comprehensive income (loss) attributable to noncontrolling interests	10	10	20	27
Comprehensive income attributable to PNC	$ 1,105	$ 1,268	$ 1,777	$ 2,311