Balance Sheet Components

6 Months Ended

Jun. 30, 2019

Balance Sheet Components [Abstract]

Balance Sheet Components

Balance Sheet Components

Contract Balances  

Accounts receivable represents amounts invoiced and revenue recognized prior to invoicing when we have satisfied our performance obligation and have the unconditional right to payment. The allowance for doubtful accounts and authorized credits is estimated based upon our assessment of various factors including historical experience, the age of the accounts receivable balances, current economic conditions and other factors that may affect our customers’ ability to pay. The allowance for doubtful accounts and authorized credits was $117 million and $106 million as of June 30, 2019 and December 31, 2018, respectively.

Deferred revenue consists of fees received related to unsatisfied performance obligations at the end of the period. Due to the generally short-term duration of contracts, the majority of the performance obligations are satisfied in the following reporting period. The amount of revenue recognized for the six month period ended June 30, 2019 that was included in the deferred revenue balance at the beginning of the period was $89 million. The amount of revenue recognized for the six month period ended June 30, 2018 that was included in the deferred revenue balance at the beginning of the period was $90 million.