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Investments - Investments Classified as Long-Term Available-for-Sale Investments and Long-Term Cost Method Investments (Detail) - USD ($) $ in Thousands | Sep. 30, 2017 | Dec. 31, 2016
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Schedule of Available-for-sale Securities and Cost-method Investments [Line Items] |  |
Investments classified as long-term | $ 10,593 | $ 9,858
Available-for-Sale Investments [Member] | Group Insurance Contracts [Member] |  |
Schedule of Available-for-sale Securities and Cost-method Investments [Line Items] |  |
Investments classified as long-term | 6,193 | 5,558
Cost-method Investments [Member] | Minority Interest in Private Company [Member] |  |
Schedule of Available-for-sale Securities and Cost-method Investments [Line Items] |  |
Investments classified as long-term | $ 4,400 | $ 4,300

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- Definition Schedule of available-for-sale securities and cost-method investments. + References No definition available. + Details
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- Definition The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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