Note 3 - Other Long-Term Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Deferred compensation plan assets	$ 15,317	$ 13,985
Prepaid expense	1,395	1,257
Other	1,182	1,099
Total	$ 17,894	$ 16,341

Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

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 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount of other miscellaneous assets expected to be realized or consumed after one year or normal operating cycle, if longer.

+ References

No definition available.

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of noncurrent assets classified as other.

+ References

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Sum of the carrying amounts as of the balance sheet date of amounts paid in advance for expenses which will be charged against earnings in periods after one year or beyond the operating cycle, if longer.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	debit
Period Type:	instant