Business Acquisitions (Narrative) (Details) (USD $)	12 Months Ended			3 Months Ended		0 Months Ended	3 Months Ended	0 Months Ended	3 Months Ended	0 Months Ended	3 Months Ended	0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 29, 2014	Jun. 30, 2013	Jun. 23, 2013	Sep. 29, 2013	Apr. 04, 2013	Sep. 30, 2012	Jul. 03, 2012	Jul. 01, 2012	Jun. 04, 2012	Jun. 21, 2013	Apr. 02, 2013
Business Acquisition [Line Items]
Goodwill, Acquired During Period		$ 55,035,000
Goodwill	81,721,000	155,916,000	100,881,000
Intangibles Impairment charges	0	2,000,000	0
Indefinite-lived intangible assets		100,000
Amortization of Intangible Assets	17,900,000	15,500,000	4,900,000
Arada Systems [Member]
Business Acquisition [Line Items]
Total purchase price					5,250,000
Purchase price, cash paid				1,100,000	4,200,000
Intangible assets, net													4,040,000
Goodwill													1,195,000
Arada Systems [Member] | Technology [Member]
Business Acquisition [Line Items]
Intangible assets, net													4,000,000
Discount rate used to calculate present value of future cash flows ( in percentage)						21.50%
Acquired intangible assets, estimated useful life ( in years)						5 years
Arada Systems [Member] | US Federal [Member]
Business Acquisition [Line Items]
Business Acquisition, Goodwill, Expected Tax Deductible Amount													700,000
Arada Systems [Member] | State [Member]
Business Acquisition [Line Items]
Business Acquisition, Goodwill, Expected Tax Deductible Amount													1,200,000
Sierra Wireless AirCard Business [Member]
Business Acquisition [Line Items]
Total purchase price					140,030,000
Goodwill, Purchase Accounting Adjustments							500,000
Intangible assets, net														69,700,000
Goodwill														53,841,000
Intangibles Impairment charges		2,000,000					2,000,000
Sierra Wireless AirCard Business [Member] | In-Process Research and Development [Member]
Business Acquisition [Line Items]
Intangible assets, net														9,500,000
Discount rate used to calculate present value of future cash flows ( in percentage)								13.00%
Sierra Wireless AirCard Business [Member] | Technology [Member]
Business Acquisition [Line Items]
Intangible assets, net														16,300,000
Discount rate used to calculate present value of future cash flows ( in percentage)								10.00%
Acquired intangible assets, estimated useful life ( in years)								4 years
In Process Research and Development achieving technological feasibility		7,500,000
Sierra Wireless AirCard Business [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Intangible assets, net														40,500,000
Discount rate used to calculate present value of future cash flows ( in percentage)								12.00%
Acquired intangible assets, estimated useful life ( in years)								8 years
Sierra Wireless AirCard Business [Member] | Noncompete Agreements [Member]
Business Acquisition [Line Items]
Intangible assets, net														2,300,000
Discount rate used to calculate present value of future cash flows ( in percentage)								12.00%
Acquired intangible assets, estimated useful life ( in years)								5 years
Sierra Wireless AirCard Business [Member] | Order Backlog [Member]
Business Acquisition [Line Items]
Intangible assets, net														1,100,000
Discount rate used to calculate present value of future cash flows ( in percentage)								10.00%
Sierra Wireless AirCard Business [Member] | US Federal [Member]
Business Acquisition [Line Items]
Business Acquisition, Goodwill, Expected Tax Deductible Amount														35,800,000
Sierra Wireless AirCard Business [Member] | Canadian [Member]
Business Acquisition [Line Items]
Business Acquisition, Goodwill, Expected Tax Deductible Amount														53,800,000
Sierra Wireless AirCard Business [Member] | State [Member]
Business Acquisition [Line Items]
Business Acquisition, Goodwill, Expected Tax Deductible Amount														2,300,000
Avaak Inc. [Member]
Business Acquisition [Line Items]
Total purchase price									24,000,000
Business Acquisition, Percentage of Voting Interests Acquired										100.00%
Purchase price, cash paid							2,400,000		21,600,000
Intangible assets, net										6,000,000
Goodwill										11,895,000
Business Acquisition, Goodwill, Expected Tax Deductible Amount										0
Deferred tax assets, net										5,937,000
Avaak Inc. [Member] | In-Process Research and Development [Member]
Business Acquisition [Line Items]
Intangible assets, net										2,000,000
IPR&D Reaching Technical Feasibility Useful Life										4 years
Avaak Inc. [Member] | Technology [Member]
Business Acquisition [Line Items]
Intangible assets, net										2,300,000
Discount rate used to calculate present value of future cash flows ( in percentage)										14.00%
Acquired intangible assets, estimated useful life ( in years)										5 years
Avaak Inc. [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Intangible assets, net										300,000
Discount rate used to calculate present value of future cash flows ( in percentage)										14.00%
Acquired intangible assets, estimated useful life ( in years)										5 years
Avaak Inc. [Member] | Trade Names and Trademarks [Member]
Business Acquisition [Line Items]
Intangible assets, net										1,400,000
Discount rate used to calculate present value of future cash flows ( in percentage)										16.00%
Acquired intangible assets, estimated useful life ( in years)										5 years
Avaak Inc. [Member] | US Federal [Member]
Business Acquisition [Line Items]
Business Acquisition, Goodwill, Expected Tax Deductible Amount										0
Avaak Inc. [Member] | State [Member]
Business Acquisition [Line Items]
Business Acquisition, Goodwill, Expected Tax Deductible Amount										0
Firetide, Inc. [Member]
Business Acquisition [Line Items]
Total purchase price											7,200,000
Purchase price, cash paid					600,000						6,600,000
Intangible assets, net												4,159,000
Goodwill												3,041,000
Firetide, Inc. [Member] | Technology [Member]
Business Acquisition [Line Items]
Discount rate used to calculate present value of future cash flows ( in percentage)												22.00%
Acquired intangible assets, estimated useful life ( in years)												5 years
Firetide, Inc. [Member] | US Federal [Member]
Business Acquisition [Line Items]
Business Acquisition, Goodwill, Expected Tax Deductible Amount												1,600,000
Firetide, Inc. [Member] | State [Member]
Business Acquisition [Line Items]
Business Acquisition, Goodwill, Expected Tax Deductible Amount												3,000,000