Restructuring Activities (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended					1 Months Ended	12 Months Ended	1 Months Ended	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2010 Outsourcing Initiative [Member]	Dec. 31, 2009 Outsourcing Initiative [Member]	Nov. 30, 2008 Network Re-Engineering [Member]	Dec. 31, 2009 Network Re-Engineering [Member]	Dec. 31, 2008 Economic Workforce Reduction [Member]	Dec. 31, 2009 Economic Workforce Reduction [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 1,981	$ 4,990	$ 2,853	$ 2,500	$ 3,400		$ 1,600		$ 1,100
Number of service centers closed due to re-engineering						40
Balanced service centers after network re-engineering						100
Reduced workforce positions								1,450