Restricted Cash and Cash Equivalents, Foreign Tender

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- Definition

Restricted Cash And Cash Equivalents, Value Added Tax Collateral Requirement

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- Definition

Restricted Cash Guaranteed Investment Certificate Used For Collateral

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- Definition

Restricted Cash Outstanding Letters of Credit Used For Collateral

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- Definition

Amount of debt securities categorized neither as held-to-maturity nor trading.

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- Definition

Amount of investments in debt securities classified as available-for-sale, expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer.

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- Definition

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- Definition

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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of 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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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, 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.

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Cash and Cash Equivalents and Available for Sale Securities - Additional Information (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2015
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 166,734	$ 541,835	$ 600,356	$ 373,173
Cash	152,000	485,700
Available for sale Securities
Fair value of available for sale securities	42,168
Available for sale securities	42,168	0
Restricted Cash
Restricted cash	5,048	5,032
Restricted cash, letter of credit - foreign taxes	3,700	3,700
Restricted cash, letter of credit - lease agreement	1,000	1,000
Restricted cash, guaranteed investment certificate for collateralizing an available credit facility	100	100
Restricted cash, foreign tender requirements	200	200
Money market funds
Cash and Cash Equivalents [Line Items]
Cash equivalents	$ 14,700	$ 56,100