|12 Months Ended|
Dec. 31, 2017
|Risks and Uncertainties [Abstract]|
The following table shows customers with revenues of 10% or greater of total third-party revenues and customers with accounts receivable balances of 10% or greater of total accounts receivable from third parties:
* Less than 10%
During the year ended December 31, 2017, revenues from external customers that were derived from domestic customers was $1.4 billion and from customers outside of the United States was $1.5 billion, of which $787 million and $666 million were from customers in Ireland and South Korea, respectively. During the year ended December 31, 2016, revenues from external customers that were derived from domestic customers was $677 million and from customers outside of the United States was $125 million. We attribute revenues from external customers to the country in which the party to the applicable agreement has its principal place of business. Substantially all of our long-lived assets are located in the United States.
The entire disclosure for any concentrations existing at the date of the financial statements that make an entity vulnerable to a reasonably possible, near-term, severe impact. This disclosure informs financial statement users about the general nature of the risk associated with the concentration, and may indicate the percentage of concentration risk as of the balance sheet date.
Reference 1: http://www.xbrl.org/2003/role/presentationRef