The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Intangible Assets - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended		3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Aggregate amortization expenses for intangible assets	$ 1,514us-gaap_AmortizationOfIntangibleAssets	$ 6,792us-gaap_AmortizationOfIntangibleAssets
Estimated aggregate amortization expense of intangible assets in 2015	316
Estimated aggregate amortization expense of intangible assets in 2016	315
Estimated aggregate amortization expense of intangible assets in 2017	315
Estimated aggregate amortization expense of intangible assets in 2018	315
Estimated aggregate amortization expense of intangible assets in 2019	314
Impairment charges	10,269us-gaap_AssetImpairmentCharges	6,378us-gaap_AssetImpairmentCharges
Fabrication facility [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment charges		617
Dawin Electronics [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment of goodwill		3,389	3,389
Dawin Electronics [Member] \| Fabrication facility [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment charges		5,870
Dawin Electronics [Member] \| Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment charges		$ 1,864	$ 1,864