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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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The total expense recognized in the period for promotion, public relations, and brand or product advertising.

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The Company and Summary of Significant Accounting Policies Narrative (Details) (USD $)	12 Months Ended			3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 29, 2013
Significant Accounting Policies [Line Items]
Cost method investment	$ 1,322,000us-gaap_CostMethodInvestments	$ 1,322,000us-gaap_CostMethodInvestments
Gain on Sale of Investments	0us-gaap_GainLossOnSaleOfInvestments	0us-gaap_GainLossOnSaleOfInvestments	3,126,000us-gaap_GainLossOnSaleOfInvestments
Goodwill impairment charges	74,196,000us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss
Standard Warranty Replacement of a Defective Product, Period	1 year
Shipping, Handling and Transportation Costs	10,500,000	11,600,000	12,100,000
Marketing and Advertising Expense	19,100,000us-gaap_MarketingAndAdvertisingExpense	18,000,000us-gaap_MarketingAndAdvertisingExpense	19,000,000us-gaap_MarketingAndAdvertisingExpense
Foreign Currency Transaction Gain (loss), net	(5,642,000)	(1,592,000)	204,000
Other than Temporary Impairment Losses, Investments	0us-gaap_ImpairmentOfInvestments	0us-gaap_ImpairmentOfInvestments	0us-gaap_ImpairmentOfInvestments
Intangibles Impairment charges	0us-gaap_AssetImpairmentCharges	2,000,000us-gaap_AssetImpairmentCharges	0us-gaap_AssetImpairmentCharges
Impairment of Intangible Assets (Excluding Goodwill)	0	2,000,000	0
Service Provider [Member]
Significant Accounting Policies [Line Items]
Goodwill impairment charges	74,196,000	0	0
Minimum [Member]
Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life	4 years
Maximum [Member]
Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years
Accounts Receivable [Member] \| Best Buy Inc [Member] \| Customer Concentration Risk [Member]
Significant Accounting Policies [Line Items]
Concentration Risk, Percentage	21.00%	21.00%
Sierra Wireless AirCard Business [Member]
Significant Accounting Policies [Line Items]
Intangibles Impairment charges		$ 2,000,000		$ 2,000,000