Note 4 - Balance Sheet Components - Other Long-term Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Deferred compensation plan assets	$ 51,759	$ 53,172
Prepaid expenses	2,261	2,311
Other	14,032	14,040
Total	$ 68,052	$ 69,523

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(17))
-URI https://asc.fasb.org/extlink&oid=120391452&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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Namespace Prefix:	us-gaap_
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Balance Type:	debit
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- Definition

Amount of noncurrent assets classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(17))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Data Type:	xbrli:monetaryItemType
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- Definition

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

+ References

+ Details

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