Consolidated Statement of Changes in Equity (unaudited) - USD ($) $ in Millions	Total		Preferred stock	Common stock	Additional paid-in capital	Retained earnings	Accumulated other comprehensive (loss), net of tax	Treasury stock	Non-redeemable noncontrolling interests of consolidated investment management funds	Redeemable non- controlling interests/ temporary equity	Cumulative Effect, Period Of Adoption, Adjustment	Cumulative Effect, Period Of Adoption, Adjustment Retained earnings	Cumulative Effect, Period Of Adoption, Adjustment Accumulated other comprehensive (loss), net of tax	Cumulative Effect, Period of Adoption, Adjusted Balance	Cumulative Effect, Period of Adoption, Adjusted Balance Preferred stock	Cumulative Effect, Period of Adoption, Adjusted Balance Common stock	Cumulative Effect, Period of Adoption, Adjusted Balance Additional paid-in capital	Cumulative Effect, Period of Adoption, Adjusted Balance Retained earnings	Cumulative Effect, Period of Adoption, Adjusted Balance Accumulated other comprehensive (loss), net of tax	Cumulative Effect, Period of Adoption, Adjusted Balance Treasury stock	Cumulative Effect, Period of Adoption, Adjusted Balance Non-redeemable noncontrolling interests of consolidated investment management funds	Cumulative Effect, Period of Adoption, Adjusted Balance Redeemable non- controlling interests/ temporary equity
Beginning balance at Dec. 31, 2018	$ 40,739	[1]	$ 3,542	$ 14	$ 27,118	$ 28,652	$ (3,171)	$ (15,517)	$ 101	$ 129	$ 0	$ 90	$ (90)	$ 40,739	$ 3,542	$ 14	$ 27,118	$ 28,742	$ (3,261)	$ (15,517)	$ 101	$ 129
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued to shareholders of noncontrolling interests										52
Redemption of subsidiary shares from noncontrolling interests										(7)
Other net changes in noncontrolling interests	108				23				85	(26)
Net income	3,018					3,001			17
Other comprehensive (loss) income attributable to The Bank of New York Mellon Corporation shareholders	368						368
Other comprehensive income (loss)	(1)									(1)
Dividends:
Common stock	(834)					(834)
Preferred stock	(120)					(120)
Repurchase of common stock	(2,286)							(2,286)
Common stock issued under employee benefit plans	22				22
Direct stock purchase and dividend reinvestment plan	11				11
Stock awards and options exercised	297				297
Ending balance at Sep. 30, 2019	$ 41,323	[1],[2]	3,542	14	27,471	30,789	(2,893)	(17,803)	203	147
Dividends:
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201602Member
Beginning balance at Dec. 31, 2018	$ 40,739	[1]	3,542	14	27,118	28,652	(3,171)	(15,517)	101	129	0	90	(90)	40,739	3,542	14	27,118	28,742	(3,261)	(15,517)	101	129
Ending balance at Dec. 31, 2019	$ 41,585	[3]	3,542	14	27,515	31,894	(2,638)	(18,844)	102	143	40	45	(5)	41,625	3,542	14	27,515	31,939	(2,643)	(18,844)	102	143
Dividends:
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201613Member
Beginning balance at Jun. 30, 2019	$ 41,699	[2]	3,542	14	27,406	30,081	(2,688)	(16,822)	166	136
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued to shareholders of noncontrolling interests										16
Other net changes in noncontrolling interests	36				2				34	(2)
Net income	1,041					1,038			3
Other comprehensive (loss) income attributable to The Bank of New York Mellon Corporation shareholders	(205)						(205)
Other comprehensive income (loss)	(3)									(3)
Dividends:
Common stock	(294)					(294)
Preferred stock	(36)					(36)
Repurchase of common stock	(981)							(981)
Common stock issued under employee benefit plans	6				6
Stock awards and options exercised	57				57
Ending balance at Sep. 30, 2019	41,323	[1],[2]	3,542	14	27,471	30,789	(2,893)	(17,803)	203	147
Beginning balance at Dec. 31, 2019	41,585	[3]	3,542	14	27,515	31,894	(2,638)	(18,844)	102	143	$ 40	$ 45	$ (5)	$ 41,625	$ 3,542	$ 14	$ 27,515	$ 31,939	$ (2,643)	$ (18,844)	$ 102	$ 143
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued to shareholders of noncontrolling interests										55
Redemption of subsidiary shares from noncontrolling interests										(17)
Other net changes in noncontrolling interests	140				(5)				145	(2)
Net income	2,871					2,867			4
Other comprehensive (loss) income attributable to The Bank of New York Mellon Corporation shareholders	1,284						1,284
Other comprehensive income (loss)	0									0
Dividends:
Common stock	(839)					(839)
Preferred stock	(146)					(146)
Repurchase of common stock	(988)							(988)
Common stock issued under employee benefit plans	21				21
Preferred stock issued	990		990
Stock awards and options exercised	210				210
Ending balance at Sep. 30, 2020	45,168	[3],[4]	4,532	14	27,741	33,821	(1,359)	(19,832)	251	179
Beginning balance at Mar. 31, 2020	41,239	[5]	3,542	14	27,644	32,601	(2,827)	(19,829)	94	140
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued to shareholders of noncontrolling interests										17
Other net changes in noncontrolling interests	3				0				3	0
Net income	965					950			15
Other comprehensive (loss) income attributable to The Bank of New York Mellon Corporation shareholders	884						884
Other comprehensive income (loss)	0									0
Dividends:
Common stock	(278)					(278)
Preferred stock	(49)					(49)
Repurchase of common stock	(3)							(3)
Common stock issued under employee benefit plans	6				6
Preferred stock issued	990		990
Stock awards and options exercised	52				52
Ending balance at Jun. 30, 2020	43,809	[4],[5]	4,532	14	27,702	33,224	(1,943)	(19,832)	112	157
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued to shareholders of noncontrolling interests										21
Redemption of subsidiary shares from noncontrolling interests										(1)
Other net changes in noncontrolling interests	132				0				132	0
Net income	944					937			7
Other comprehensive (loss) income attributable to The Bank of New York Mellon Corporation shareholders	584						584
Other comprehensive income (loss)	2									2
Dividends:
Common stock	(279)					(279)
Preferred stock	(61)					(61)
Common stock issued under employee benefit plans	6				6
Stock awards and options exercised	33				33
Ending balance at Sep. 30, 2020	$ 45,168	[3],[4]	$ 4,532	$ 14	$ 27,741	$ 33,821	$ (1,359)	$ (19,832)	$ 251	$ 179

[1] Includes total The Bank of New York Mellon Corporation common shareholders’ equity of $37,096 million at Dec. 31, 2018 and $37,578 million at Sept. 30, 2019.

[2] Includes total The Bank of New York Mellon Corporation common shareholders’ equity of $37,991 million at June 30, 2019 and $37,578 million at Sept. 30, 2019.

[3] Includes total The Bank of New York Mellon Corporation common shareholders’ equity of $37,941 million at Dec. 31, 2019 and $40,385 million at Sept. 30, 2020.

[4] Includes total The Bank of New York Mellon Corporation common shareholders’ equity of $39,165 million at June 30, 2020 and $40,385 million at Sept. 30, 2020.

[5] Includes total The Bank of New York Mellon Corporation common shareholders’ equity of $37,603 million at March 31, 2020 and $39,165 million at June 30, 2020.