Condensed Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Condensed Consolidated Statements of Cash Flows
Cash and cash equivalents	$ 476,812	$ 643,095
Restricted cash included in other current assets	$ 306	$ 307
Restricted Cash and Cash Equivalents, Asset, Statement of Financial Position [Extensible List]	Other Assets, Current	Other Assets, Current
Restricted cash, noncurrent	$ 8,610	$ 2,552
Total cash, cash equivalents and restricted cash	$ 485,728	$ 645,954

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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