Balance Sheet Components, Other Non-Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Balance Sheet Related Disclosures [Abstract]
Deferred income taxes	$ 7,990	$ 7,360
Other non-current liabilities	6,021	4,667
Deferred compensation liability	4,620	4,409
Total	$ 18,631	$ 16,436

No definition available.

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable beyond one year (or the operating cycle, if longer).

+ References

No definition available.

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- Definition

Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=84176650&loc=d3e31931-109318

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Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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- Definition

Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are expected to be paid after one year (or the normal operating cycle, if longer), from the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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