Legal Proceedings (Details) (Class Action Complaint [Member], USD $) In Millions, unless otherwise specified	1 Months Ended		4 Months Ended		6 Months Ended
	Sep. 30, 2010	Jan. 31, 2010	Dec. 31, 2009	Dec. 31, 2008	Jun. 30, 2009	Sep. 28, 2010	Jan. 15, 2010	Aug. 29, 2005	Jan. 13, 2005
Class Action Complaint [Member]
Loss Contingencies [Line Items]
Original District Court judgment, pre-judgment interest rate (in hundredths)									5.00%
Original District Court judgment, back pay awarded to plaintiffs								$ 3.4
Original District Court judgment, estimated attorney fees to be awarded to plaintiffs, maximum								2.5
Interim District Court judgment, attorney fees and costs awarded to plaintiffs					5.8
Loss provision recorded during the period	1.0		1.0	6.0	5.0
Final District Court judgment, damages awarded to plaintiffs							3.3
Final District Court judgment, pre-judgment interest awarded to plaintiffs							2.2
Final District Court judgment, post-judgment interest rate (in hundredths)							0.41%
Previous estimate of total liability for damages and interest							5.2
Number of days plaintiffs were given to submit supplemental request							14D
Motion for supplemental award for attorney's fees, cost and expenses, amount sought		0.7
Final District Court judgment, attorney's fees, costs, and expenses awarded to plaintiffs						$ 0.7