v3.3.1.900
Variable Interest Entities Reflects adoption of ASU 2015-12 - Balances Relating to Variable Interest Entities in which BlackRock is Not Primary Beneficiary (Detail) - Variable Interest Entity, Not Primary Beneficiary [Member] - USD ($)
Dec. 31, 2015
Dec. 31, 2014
Investments [Member]    
Variable Interest Entity [Line Items]    
Sponsored investment products $ 64,000,000  
CDOs/CLOs   $ 0
Collective trusts   0
Other   57,000,000
Total   57,000,000
Advisory Fee Receivables [Member]    
Variable Interest Entity [Line Items]    
Sponsored investment products 3,000,000  
CDOs/CLOs   2,000,000
Collective trusts   191,000,000
Other   177,000,000
Total   370,000,000
Other Net Assets (Liabilities) [Member]    
Variable Interest Entity [Line Items]    
Sponsored investment products (7,000,000)  
CDOs/CLOs   (5,000,000)
Collective trusts   0
Other   (3,000,000)
Total   (8,000,000)
Maximum Risk of Loss [Member]    
Variable Interest Entity [Line Items]    
Sponsored investment products $ 84,000,000  
CDOs/CLOs   19,000,000
Collective trusts   191,000,000
Other   234,000,000
Total   $ 444,000,000