Consolidated Comprehensive Income Statement (unaudited) - USD ($) $ in Millions		3 Months Ended			6 Months Ended
		Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income		$ 965	$ 962	$ 1,021	$ 1,927	$ 1,977
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments		115	(369)	10	(254)	39
Unrealized gain on assets available-for-sale:
Unrealized gain arising during the period		753	183	287	936	526
Reclassification adjustment		(7)	(7)	(5)	(14)	(6)
Total unrealized gain on assets available-for-sale		746	176	282	922	520
Defined benefit plans:
Net (loss) arising during the period		0	0	0	0	(9)
Amortization of prior service credit, net loss and initial obligation included in net periodic benefit cost		19	18	10	37	20
Total defined benefit plans		19	18	10	37	11
Net unrealized gain (loss) on cash flow hedges		4	(11)	0	(7)	5
Total other comprehensive income (loss), net of tax	[1]	884	(186)	302	698	575
Total comprehensive income		1,849	776	1,323	2,625	2,552
Total comprehensive income		(15)	18	(4)	3	(14)
Other comprehensive loss (income) attributable to noncontrolling interests		0	2	0	2	(2)
Comprehensive income applicable to shareholders of The Bank of New York Mellon Corporation		1,834	796	1,319	2,630	2,536
Other comprehensive (loss) income attributable to The Bank of New York Mellon Corporation shareholders		$ 884	$ (184)	$ 302	$ 700	$ 573

[1] Other comprehensive income (loss) attributable to The Bank of New York Mellon Corporation shareholders was $884 million for the quarter ended June 30, 2020, $(184) million for the quarter ended March 31, 2020, $302 million for the quarter ended June 30, 2019, $700 million for the six months ended June 30, 2020 and $573 million for the six months ended June 30, 2019.