Note 6 - Balance Sheet Components - Other Long-term Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024
Deferred compensation plan liabilities	$ 103,954				$ 93,653
Operating lease liabilities	19,972				12,974
Dividend equivalents	3,909				4,943
Total	$ 127,835	$ 117,380	$ 113,449	$ 105,814	$ 111,570

Long-term accrued dividend equivalents.

No definition available.

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- Definition

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.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-1

+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(24))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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