v3.3.1.900
Intangible Assets - Finite-lived Intangible Assets (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]    
Finite-lived intangible assets - Remaining Weighted-Average Estimated Useful Life 3 years 8 months 12 days 3 years 9 months 18 days
Finite-lived intangible assets - Gross Carrying Amount $ 1,009 $ 1,396
Finite-lived intangible assets - Accumulated Amortization 745 1,040
Finite-lived intangible assets - Net Carrying Amount $ 264 $ 356
Management Contracts [Member]    
Finite-Lived Intangible Assets [Line Items]    
Finite-lived intangible assets - Remaining Weighted-Average Estimated Useful Life 3 years 8 months 12 days 3 years 9 months 18 days
Finite-lived intangible assets - Gross Carrying Amount $ 1,003 $ 1,390
Finite-lived intangible assets - Accumulated Amortization 741 1,036
Finite-lived intangible assets - Net Carrying Amount $ 262 $ 354
Intellectual Property [Member]    
Finite-Lived Intangible Assets [Line Items]    
Finite-lived intangible assets - Remaining Weighted-Average Estimated Useful Life 2 years 7 months 6 days 3 years 7 months 6 days
Finite-lived intangible assets - Gross Carrying Amount $ 6 $ 6
Finite-lived intangible assets - Accumulated Amortization 4 4
Finite-lived intangible assets - Net Carrying Amount $ 2 $ 2