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Cash and Cash Equivalents, Restricted, Fair Value Disclosure

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
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-Topic 320
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Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
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Fair value portion 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.

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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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Fair Value Measurements (Balance Measured at Fair Value) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Current	$ 500	$ 500
Assets
Restricted cash	26,112	24,175	$ 21,640	$ 16,488
Investment available for sale	15,100	17,300
Liabilities
Fair Value, Discount Amount, Available for sales securities	2,900	2,900
Fair Value, Measurements, Recurring [Member]
Assets
Cash and cash equivalents	632,808	203,104
Restricted cash	26,112	24,175
Investment available for sale	15,591	17,752
Liabilities
Business Combination, Contingent Consideration, Liability	2,577	2,887
Fair Value, Measurements, Recurring [Member] \| Level 1
Assets
Cash and cash equivalents	632,808	203,104
Investment available for sale	0	0
Liabilities
Business Combination, Contingent Consideration, Liability	0	0
Fair Value, Measurements, Recurring [Member] \| Level 2
Assets
Cash and cash equivalents	0	0
Restricted cash	0	0
Investment available for sale	0	0
Liabilities
Business Combination, Contingent Consideration, Liability	0	0
Fair Value, Measurements, Recurring [Member] \| Level 3
Assets
Cash and cash equivalents	0	0
Restricted cash	0	0
Investment available for sale	15,591	17,752
Liabilities
Business Combination, Contingent Consideration, Liability	$ 2,577	$ 2,887