INCOME TAXES - Significant components of the deferred tax assets and liabilities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Deferred tax assets:
Net operating loss carryforwards	$ 65,830	$ 75,622
Tax credit carryforwards	54,887	50,704
Deferred revenue	1,434	1,537
Capitalized research and development costs	315	394
Intangibles	19,254	21,175
Share-based compensation	5,232	5,808
Accrued compensation	3,441	1,775
Accrued warranty	612	446
Inventory reserves	6,835	5,664
Reserves and other	11,150	13,216
Depreciation and amortization	5,958	6,731
Other, net	7,518	6,069
Total deferred tax assets	182,466	189,141
Valuation allowance for deferred tax assets	(135,697)	(130,979)
Net deferred tax assets	46,769	58,162
Net deferred tax liabilities:
Acquired intangible assets	(39,836)	(45,397)
Acquired tangible assets	(1,993)	(7,701)
Cancellation of debt	(9,654)	(9,669)
Foreign earnings	(2,923)	(3,282)
Other, net	(1,378)	(1,296)
Total deferred tax liabilities	(55,784)	(67,345)
Net deferred tax (liabilities) assets	$ (9,015)	$ (9,183)