Note 5 - Balance Sheet Components (Tables)

12 Months Ended

Dec. 31, 2018

Notes Tables

Schedule of Inventory, Current [Table Text Block]

	December 31,
	2018		2017
Raw materials	$	43,017	$	20,573
Work in process		38,674		40,030
Finished goods		54,693		38,678
Total	$	136,384	$	99,281

Schedule of Other Current Assets [Table Text Block]

	December 31,
	2018		2017
Prepaid wafer purchase (1)	$	-	$	6,217
Prepaid wafer refund receivable (1)		4,297		-
Other prepaid expense		3,425		2,742
Assets for product returns (2)		1,602		-
Interest receivable		1,441		1,352
Value-added tax receivable		423		1,235
Other		743		1,216
Total	$	11,931	$	12,762

Property, Plant and Equipment [Table Text Block]

	December 31,
	2018			2017
Production equipment and software	$	120,645		$	110,971
Buildings and improvements		100,135			100,990
Land		16,724			16,883
Transportation equipment		12,948			11,443
Leasehold improvements		4,755			3,321
Furniture and fixtures		4,341			3,641
Property and equipment, gross		259,548			247,249
Less: accumulated depreciation and amortization		(109,547	)		(102,613	)
Total	$	150,001		$	144,636

Schedule of Other Assets, Noncurrent [Table Text Block]

	December 31,
	2018		2017
Deferred compensation plan assets	$	31,970	$	28,080
Prepaid expense		2,713		897
Other		1,185		1,091
Total	$	35,868	$	30,068

Schedule of Accrued Liabilities [Table Text Block]

	December 31,
	2018		2017
Dividends and dividend equivalents	$	15,044	$	9,248
Income tax payable		7,018		2,861
Stock rotation and sales returns		5,363		2,647
Warranty		4,564		2,416
Customer prepayments		2,520		4,742
Commissions		1,369		938
Sales rebate		236		1,036
Deferred income		-		1,845
Other		2,848		1,774
Total	$	38,962	$	27,507

Other Noncurrent Liabilities [Table Text Block]

	December 31,
	2018		2017
Deferred compensation plan liabilities	$	32,283	$	28,087
Dividend equivalents		6,145		4,881
Other		97		56
Total	$	38,525	$	33,024