Note 5 - Balance Sheet Components (Tables)

12 Months Ended

Dec. 31, 2017

Notes Tables

Schedule of Inventory, Current [Table Text Block]

	December 31,
	2017		2016
Raw materials	$	20,573	$	14,599
Work in process		40,030		26,048
Finished goods		38,678		30,822
Total	$	99,281	$	71,469

Schedule of Other Current Assets [Table Text Block]

	December 31,
	2017		2016
Prepaid wafer purchase	$	6,217	$	5,000
Other prepaid expense		2,742		2,249
Interest receivable		1,352		966
Value-added tax receivable		1,235		263
Other		1,216		565
Total	$	12,762	$	9,043

Property, Plant and Equipment [Table Text Block]

	December 31,
	2017			2016
Production equipment and software	$	110,971		$	95,565
Buildings and improvements		100,990			48,964
Transportation equipment		11,443			11,291
Land		16,883			8,285
Furniture and fixtures		3,641			3,518
Leasehold improvements		3,321			2,838
Property and equipment, gross		247,249			170,461
Less: accumulated depreciation and amortization		(102,613	)		(85,290	)
Total	$	144,636		$	85,171

Schedule of Other Assets, Noncurrent [Table Text Block]

	December 31,
	2017		2016
Deferred compensation plan assets	$	28,080	$	20,288
Prepaid wafer purchase		-		5,000
Other prepaid expense		897		1,117
Other		1,091		1,006
Total	$	30,068	$	27,411

Schedule of Accrued Liabilities [Table Text Block]

	December 31,
	2017		2016
Dividends and dividend equivalents	$	9,248	$	8,946
Customer prepayments		4,742		3,246
Income tax payable		2,861		1,239
Stock rotation reserve		2,647		1,937
Warranty		2,416		1,030
Deferred income		1,845		3,553
Sales rebate		1,036		441
Commissions		938		1,008
Other		1,774		1,516
Total	$	27,507	$	22,916

Other Noncurrent Liabilities [Table Text Block]

	December 31,
	2017		2016
Deferred compensation plan liabilities	$	28,087	$	19,836
Dividend equivalents		4,881		3,294
Other		56		89
Total	$	33,024	$	23,219