v3.8.0.1
Balance Sheet Account Details - Summary of Contractual Maturities of Available-for-sale Debt Securities (Details)
$ in Millions
Dec. 31, 2017
USD ($)
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]  
Due within one year $ 686
After one but within five years 234
Total $ 920