Business Acquisitions (Narrative 1) (Details) (USD $)	3 Months Ended							3 Months Ended						0 Months Ended
	Apr. 01, 2012	Apr. 03, 2011	Apr. 15, 2011	Apr. 01, 2012 Leaf Networks, LLC [Member]	Apr. 03, 2011 Leaf Networks, LLC [Member]	Mar. 28, 2010 Leaf Networks, LLC [Member]	Jan. 15, 2010 Leaf Networks, LLC [Member] Y	Apr. 01, 2012 Leaf Networks, LLC [Member] Existing Technology [Member] Y	Apr. 01, 2012 Leaf Networks, LLC [Member] US Federal [Member]	Apr. 01, 2012 Leaf Networks, LLC [Member] State [Member]	Apr. 01, 2012 Leaf Networks, LLC [Member] Additional Payment [Member]	Apr. 03, 2011 Leaf Networks, LLC [Member] Additional Payment [Member]	Apr. 15, 2011 Westell Technologies, Inc. [Member]	Apr. 15, 2011 Westell Technologies, Inc. [Member] Customer Contracts And Related Relationships [Member] Y	Apr. 15, 2011 Westell Technologies, Inc. [Member] Core Technology [Member] Y	Apr. 15, 2011 Westell Technologies, Inc. [Member] Order Backlog [Member]	Apr. 15, 2011 Westell Technologies, Inc. [Member] US Federal [Member]	Apr. 15, 2011 Westell Technologies, Inc. [Member] State [Member]
Business Acquisition [Line Items]
Aggregate purchase price			$ 37,009,000	$ 2,900,000			$ 2,100,000						$ 37,009,000
Purchase price, cash paid					100,000	2,000,000					500,000	400,000
Total additional payout							900,000
Total additional payout, period (in years)							3
Present value of potential additional payments						800,000
Acquired intangible assets				2,000,000				2,000,000					19,500,000	15,700,000	3,700,000	100,000
Goodwill				900,000									11,746,000
Goodwill deductable for income tax purposes									500,000	900,000							10,600,000	11,700,000
Discount rate used to calculate present value of future cash flows (percentage)														19.00%	16.00%	3.30%
Acquired intangible assets, estimated useful life (years)								7						8	4
Intangible assets, amortized expense	$ 1,000,000	$ 1,400,000