v3.19.3.a.u2
Investments and Fair Value Measurement - Fair Value of Unobservable Inputs, Assets (Details)
$ in Millions
12 Months Ended
Dec. 31, 2019
USD ($)
Non-marketable Debt Securities  
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]  
Balance as of December 31, 2018 $ 2,370
Total net gains (losses)  
Included in earnings (8)
Included in other comprehensive income (loss) 4
Purchases 4
Transfers 0
Balance as of December 31, 2019 2,370
Non-marketable equity securities  
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]  
Balance as of December 31, 2018 0
Total net gains (losses)  
Included in earnings 11
Included in other comprehensive income (loss) 0
Purchases 56
Transfers 31
Balance as of December 31, 2019 $ 98