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Investments - Investments Classified as Long-Term Available-for-Sale Investments and Long-Term Cost Method Investments (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Schedule of Available-for-sale Securities and Cost-method Investments [Line Items]
Investments classified as long-term	$ 10,401	$ 10,290
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	6,001	5,890
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	$ 4,400

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- Definition

Schedule of available-for-sale securities and cost-method investments.

+ References

No definition available.

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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://fasb.org/us-gaap/role/ref/legacyRef
-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

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