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Employee Benefit Plans - Additional Information (Detail) - USD ($)
shares in Millions, $ in Millions
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]      
Accumulated benefit obligation for all defined benefit plans $ 5,400 $ 5,200  
Recognized cost of defined contribution plans, excluding the ESOP $ 224 $ 209 $ 198
Shares of stock owned by Employee Stock Ownership Plan 5.7 6.0  
Fair value of shares total ESOP assets $ 273 $ 251  
The Bank of New York Mellon Corporation 401(k) Savings Plan      
Defined Benefit Plan Disclosure [Line Items]      
401(k) Employer matching contribution, percent match, first 4% 100.00%    
401(k) Employer matching contribution, percent match, remaining 2% 50.00%    
401(k), Employer non-elective contribution based on earnings (percent) 2.00%    
401(k), shares of common stock owned 14.2 15.6  
401(k), fair value of total assets $ 5,700 $ 5,200  
Maximum | The Bank of New York Mellon Corporation 401(k) Savings Plan      
Defined Benefit Plan Disclosure [Line Items]      
401(k) Employer matching contribution (percent) 5.00%    
Domestic Healthcare Benefits      
Defined Benefit Plan Disclosure [Line Items]      
Assumed healthcare cost trend rate used in determining benefit expense for 2017 (percent) 6.25%    
Assumed healthcare cost trend rate used in determining benefit expense for 2022 (percent) 4.75%    
Change in the post-retirement benefit obligation as a result of an increase of one percentage point in the assumed medical trend rate (less than one million) $ 10    
Change in the post-retirement benefit obligation as a result of an increase of one percentage point in the assumed medical trend rate, percentage increase (percent) 6.00%    
Change in the post-retirement service cost plus interest cost as a result of an increase of one percentage point in the assumed medical trend rate (less than one million) $ 1    
Change in the post-retirement service cost plus interest cost as a result of an increase of one percentage point in the assumed medical trend rate, percentage increase (percent) 6.00%    
Change in the post-retirement benefit obligation as a result of a decrease of one percentage point in the assumed medical trend rate (less than one million) $ 9    
Change in the post-retirement benefit obligation as a result of a decrease of one percentage point in the assumed medical trend rate, percentage decrease (percent) 5.00%    
Change in the post-retirement service cost plus interest cost as a result of a decrease of one percentage point in the assumed medical trend rate (less than one million) $ 1    
Change in the post-retirement service cost plus interest cost as a result of a decrease of one percentage point in the assumed medical trend rate, percentage decrease (percent) 5.00%    
Cash contributions expected to be made to fund defined benefit plans in the next fiscal year $ 13    
Foreign Healthcare Benefits      
Defined Benefit Plan Disclosure [Line Items]      
Change in the post-retirement benefit obligation as a result of an increase of one percentage point in the assumed medical trend rate (less than one million) 1    
Change in the post-retirement service cost plus interest cost as a result of an increase of one percentage point in the assumed medical trend rate (less than one million) 1    
Change in the post-retirement benefit obligation as a result of a decrease of one percentage point in the assumed medical trend rate (less than one million) 1    
Change in the post-retirement service cost plus interest cost as a result of a decrease of one percentage point in the assumed medical trend rate (less than one million) 1    
Cash contributions expected to be made to fund defined benefit plans in the next fiscal year 1    
Domestic pension benefits      
Defined Benefit Plan Disclosure [Line Items]      
Cash contributions expected to be made to fund defined benefit plans in the next fiscal year $ 22    
Domestic pension benefits | Equity securities      
Defined Benefit Plan Disclosure [Line Items]      
Percentage of plan asset, cash equivalents, lower limit (percent) 30.00%    
Percentage of plan asset, cash equivalents, upper limit (percent) 70.00%    
Domestic pension benefits | Fixed income      
Defined Benefit Plan Disclosure [Line Items]      
Percentage of plan asset, cash equivalents, lower limit (percent) 20.00%    
Percentage of plan asset, cash equivalents, upper limit (percent) 50.00%    
Domestic pension benefits | Cash and Cash Equivalents      
Defined Benefit Plan Disclosure [Line Items]      
Percentage of plan asset, cash equivalents, lower limit (percent) 0.00%    
Percentage of plan asset, cash equivalents, upper limit (percent) 5.00%    
Foreign pension benefits      
Defined Benefit Plan Disclosure [Line Items]      
Cash contributions expected to be made to fund defined benefit plans in the next fiscal year $ 64