Segment Information Revenue by Major Customer (Details)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Nokia Siemens Networks [Member]
Revenue, Major Customer [Line Items]
Entity-Wide Revenue, Major Customer, Percentage	22.50%	35.10%	37.40%
NEC [Member]
Revenue, Major Customer [Line Items]
Entity-Wide Revenue, Major Customer, Percentage	11.10%		10.00%

Percentage of revenue generated from a single external customer that accounts for 10 percent or more of an entity's revenues.

No definition available.

Name:	us-gaap_EntityWideRevenueMajorCustomerPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration