Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 14,284	$ 16,830
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	9,788	9,346
Share-based compensation expense	5,076	5,330
Excess tax benefits from stock-based awards	(418)	(162)
Impairment of technology	0	1,000
Loss (gain) on disposal of assets	(33)	1
Deferred income tax provision	(3,133)	(1,939)
Changes in operating assets and liabilities
Accounts receivable	(3,534)	(6,533)
Inventories	(1,691)	(1,366)
Income taxes receivable	(351)	4,392
Prepaid expenses and other assets	(434)	(303)
Accounts payable	(6,368)	1,327
Income taxes payable	172	(442)
Other current liabilities	2,089	341
Deferred income on shipments to distributors	6,725	(1,202)
Net cash provided by operating activities	22,172	26,620
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property, plant and equipment	(5,797)	(6,221)
Purchases of intangible assets	(57)	0
Purchases of investments	(50,079)	(41,408)
Proceeds from sale and maturities of investments	57,010	41,808
Change in restricted cash	(808)	0
Net cash provided by (used in) investing activities	(5,841)	(22,260)
CASH FLOWS FROM FINANCING ACTIVITIES:
Repayments of debt	0	(282)
Proceeds from the issuance of common stock	3,743	2,730
Repurchases of common stock	(13,177)	(28,430)
Payment of cash dividends	(5,371)	(7,135)
Purchase of stock for withholding taxes on vested restricted stock	(701)	(454)
Excess tax benefits from stock-based awards	418	162
Net cash used in financing activities	(15,088)	(33,409)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1,243	(29,049)
CASH AND CASH EQUIVALENTS - Beginning of period	27,281	60,610
CASH AND CASH EQUIVALENTS - End of period	28,524	31,561
PhaseLink Acquisition [Member]
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of PhaseLink’s net assets, net of cash acquired	0	(16,439)
Discera, Inc. [Member]
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of PhaseLink’s net assets, net of cash acquired	$ (6,110)	$ 0